16M Series 3, 16, 18M Series 3 and 18 Motor Grader Power Train System Caterpillar


Power Train System
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1.1. Transmission Components
2.1. Transmission Control System
3.1. Transmission Lubrication
4.1. Transmission Clutch Engagement
5.1. Modulating Valve
6.2. General Information
7.2. No Signal
8.2. Less than Maximum Signal
9.2. Maximum Signal
10.1. Transmission Relief Valve
11.1. Transmission Power Flow
12.2. General Information
13.2. First Speed Forward
14.2. Second Speed Forward
15.2. Third Speed Forward
16.2. Fourth Speed Forward
17.2. Fifth Speed Forward
18.2. Sixth Speed Forward
19.2. Seventh Speed Forward
20.2. Eighth Speed Forward
21.2. Neutral
22.2. First Speed Reverse
23.2. Second Speed Reverse
24.2. Third Speed Reverse
25.2. Fourth Speed Reverse
26.2. Fifth Speed Reverse
27.2. Sixth Speed Reverse
28.1. Speed Sensors
29.1. Transmission Controls

This part of the manual will cover the mechanical, hydraulic, and electrical operation of the transmission control valve and clutch groups. Refer to the following sections for complete information on transmission operation.

Transmission Components

This section highlights the specific location of components that will be covered in this part of the manual.



Illustration 1g03535897
Transmission control valves and relief valve
(1) Transmission relief valve


Illustration 2g03535898
Transmission countershafts


Illustration 3g03535900
Transmission speed sensors
(2) Input speed sensor
(3) Intermediate speed sensors
(4) Transmission speed sensor
(5) Output speed sensors


Illustration 4g03535901
Transmission temperature sensor


Illustration 5g03535902
Pedal group and transmission modulation pedal position sensors
(6) Transmission modulation pedal position sensor
(7) Transmission modulation pedal position switch


Illustration 6g03535903
Transmission controls
(8) Upshift
(9) Downshift
(10) FNR switch

Transmission Control System



Illustration 7g03536096
Transmission Lubrication
(1) Transmission oil filter
(2) Oil cooler
(3) Temperature sensor
(4) Transmission main relief valve
(5) Oil filter bypass valve (transmission)
(6) Transmission lubrication
(7) Oil cooler bypass valve
(8) Parking brake solenoid
(9) Pressure sensor for the parking brake
(10) Gear pump
(10A) Transmission charging section
(10B) Transmission scavenge section
(11) Transmission lubrication relief valve
(12) Parking brake
(13) Differential lock valve
(14) Magnetic screen (differential)
(15) Magnetic screen (transmission)
(16) Engine flywheel gear case
(17) Differential lock
(18) Differential case
(19) Transmission sump
(20) Modulating valve for clutch 1
(21) Modulating valve for clutch 2
(22) Modulating valve for clutch 3
(23) Modulating valve for clutch 4
(24) Modulating valve for clutch 5
(25) Modulating valve for clutch 6
(26) Modulating valve for clutch 7
(27) Modulating valve for clutch 8
(DD) Parking brake lubrication

The oil that is used for the operation and the lubrication of the transmission is made available by gear pump (10). Gear pump (10) also provides oil for the lubrication of the differential and the lubrication of the engine flywheel. Gear pump (10) turns from power that is transferred to the transmission by the engine. The two main hydraulic reservoirs in the power train are differential case (18) and transmission sump (19).

Transmission charging section (10A) of gear pump (10) pulls oil from differential case (18) through magnetic screen (14). Pressure oil from transmission section (10A) of gear pump (10) is filtered by transmission filter (1) prior to being used to operate the following components:

  • Eight modulating valves (Electronic Clutch Pressure Control)

  • Differential lock valve (13)

  • Transmission lubrication (6)

  • Main relief valve (4)

  • Parking brake (12)

Control of the transmission is achieved by electronically activated modulating valves that allow oil to fill the various clutches in the transmission. Differential lock valve (13) is used to control differential lock (17) in the differential. Differential lock valve (13) is located on the outside housing of differential case. Pressure oil for the release of the parking brake is supplied by gear pump (10).

Reference: For more information on the parking brake, please refer to the Power Train Systems Operations, "Parking Brake".

Transmission scavenge section (10B) of gear pump (10) pulls oil from transmission sump (19) through magnetic screen (15) for the lubrication of the differential.

Transmission Lubrication



Illustration 8g01575233
Lubrication of the input shaft and a clutch shaft
(29) Input shaft
(30) Passage for lubrication of the shaft
(31) Lubrication passage
(32) Lubrication passage
(33) Lubrication passage
(34) Lubrication passage
(35) Lubrication passage
(36) Passage for lubrication of the shaft
(37) Clutch shaft
(38) Lubrication passage
(39) Lubrication passage
(40) Lubrication passage
(41) Lubrication passage
(51) Slider
(CC) Lubrication oil

Input shaft (29) receives lubrication from oil cooler (2). The oil flows through the center of each shaft. There are five passages that are connected to the center passage of input shaft (29). Lubricating oil flows through passage (31) in order to lubricate the splines on input shaft (29). Lubricating oil flows through passage (33) and passage (35) in order to lubricate the gears that transfer power to the clutch shafts. Passage (32) provides lubricating oil to the inner bearing and passage (34) provides lubrication oil for the inner race.

Clutch shaft (37) receives lubrication from oil cooler (2). The oil flows through the center of each shaft. There are four passages that are connected to the center passage of the clutch shaft (37). Lubricating oil flows through passage (38) and passage (39) in order to lubricate the gears that transfer power from the input shaft. When a clutch is engaged, slider (51) shifts in order to allow lubrication oil (CC) to enter the clutch through passage (40) and passage (41). Passage (40) and passage (41) are used to send lubrication oil (CC) to the clutch plates for lubrication and cooling. When a clutch is not engaged, slider (51) blocks passage (40) and passage (41).

Additional lubrication is provided by splash lubrication and by leakage oil. The leakage oil will return to transmission sump (19).

Transmission Clutch Engagement



Illustration 9g01575334
The transmission in fifth speed forward with clutch 1, clutch 6, and clutch 8 engaged.
(25) Clutch 6
(27) Clutch 8
(42) Clutch oil passage
(43) Clutch shaft
(44) Clutch oil passage
(45) Clutch oil passage
(46) Clutch piston
(47) Clutch oil passage
(47) Clutch oil passage
(48) Gear
(49) Clutch friction discs
(50) Clutch plate
(AA) Pressure oil
(BB) Tank oil
(CC) Lubrication oil

Hydraulic fluid (AA) from the transmission charge pump section of the two-section gear pump travels through passage (44) and passage (47). The fluid exerts pressure upon clutch piston (46). Clutch piston (46) pushes clutch plates (50) and clutch friction discs (49) together. This creates a mechanical connection between clutch shaft (43) and gear (48).

The hydraulic oil in the clutches that are not engaged is sent back to the sump and the oil becomes tank oil (BB).

Modulating Valve

General Information



Illustration 10g01310748
(1) Modulating valve for clutch 1 (forward high)
(2) Modulating valve for clutch 2 (forward low)
(3) Modulating valve for clutch 3 (reverse)
(4) Modulating valve for clutch 4 (second speed)
(5) Modulating valve for clutch 5 (third speed)
(6) Modulating valve for clutch 6 (first speed)
(7) Modulating valve for clutch 7 (low range)
(8) Modulating valve for clutch 8 (high range)


Illustration 11g01113926
Modulating valve (transmission clutch)

The clutch modulating valves are mounted on the rear of the transmission on the left side of the machine. There is one modulating valve for each of the eight transmission clutches. Refer to Illustration 10 for the location of the following modulating valves:

  • Modulating valve for clutch 1 (1) (forward high)

  • Modulating valve for clutch 2 (2) (forward low)

  • Modulating valve for clutch 3 (3) (reverse)

  • Modulating valve for clutch 4 (4) (second speed)

  • Modulating valve for clutch 5 (5) (third speed)

  • Modulating valve for clutch 6 (6) (first speed)

  • Modulating valve for clutch 7 (7) (low range)

  • Modulating valve for clutch 8 (8) (high range)

Each of the modulating valves are controlled by a solenoid. The solenoids are controlled by the machine electronic control module (ECM). The modulating valves are used by the machine ECM to directly modulate the oil pressure that is sent to each individual clutch. When the operator selects a direction and a speed, the machine ECM sends a pulse width modulated signal (PWM) in order to vary the current to the solenoid on the modulating valve. The amount of current that is sent to the solenoid regulates the amount of oil pressure that is supplied to the selected clutch. When the machine ECM sends the maximum current to the solenoid, the oil pressure in the clutch is at the maximum. When no current is sent to the modulating valve, the clutch will receive no oil pressure from the modulating valve.

In order for the machine to move, one solenoid for a speed clutch, one solenoid for a direction clutch, and one solenoid for a range clutch must be energized.

Note: The solenoid coils are not designed to be operated at 24 DCV directly. The machine ECM sends a 24 Volt PWM signal at a duty cycle which provides an average voltage of about 12 Volts to the solenoid coils. Do not energize the solenoid coils with 24 DCV (+battery). The life of the solenoid coils will be drastically reduced if the solenoid coils are energized with 24 DCV (+battery). If the solenoid coils must be energized by a source that is different from the machine ECM, use 12 DCV to energize the solenoid coils.

No Signal



Illustration 12g01338964
(9) Ball
(10) Chamber
(11) Orifice
(12) Test port
(13) Passage
(14) Valve spool
(15) Spring
(16) Chamber
(17) Passage
(18) Passage from the pump
(19) Passage to the clutch
(20) Passage to the tank
(21) Drain orifice
(22) Pin
(23) Solenoid
(AA) Pump oil
(BB) Return oil

When the machine ECM requires a clutch to be disengaged, there is no flow of electric current to solenoid (23).

Pump oil (AA) flows into the valve body from pump passage (18). Oil then flows into passage (17), through orifice (11) and into chamber (10). Since there is no signal that is sent to solenoid (23), pin (22) cannot hold ball (9) against orifice (21). The oil flows through orifice (21) past ball (9) to tank passage (20). The oil in tank passage (20) becomes return oil (BB).

Spring (15) holds valve spool (14) to the left. When valve spool (14) is shifted to the left, the oil in passage (19) flows to tank passage (20). When the oil in passage (19) is vented to the tank, the clutch cannot be engaged. The oil in pump passage (18) is blocked from entering passage (19).

Less than Maximum Signal



Illustration 13g01338972
(9) Ball
(10) Chamber
(11) Orifice
(12) Test port
(13) Passage
(14) Valve spool
(15) Spring
(16) Chamber
(17) Passage
(18) Passage from the pump
(19) Passage to the clutch
(20) Passage to the tank
(21) Drain orifice
(22) Pin
(23) Solenoid
(AA) Pump oil
(BB) Return oil
(CC) Pilot oil

When the machine ECM requires a clutch to be engaged, a signal is sent to the solenoid (23). The strength of the signal is proportional to the desired clutch pressure.

When the signal is sent to the solenoid, pin (22) moves to the right and pin (22) forces ball (9) toward orifice (21). When ball (9) moves toward orifice (21), the flow of return oil (BB) into tank passage (20) is restricted. Pressure in chamber (10) increases and pump oil (AA) acts as pilot oil (CC). The pressure moves valve spool (14) to the right against the force of spring (15).

When valve spool (14) moves to the right, pump oil (AA) in pump passage (18) enters passage (19). The valve spool blocks the flow of oil from passage (19) to tank passage (20). The clutch pressure will increase due to the flow of pump oil (AA) into passage (19). The oil in passage (19) also flows through passage (13) into chamber (16).

Initially, the machine ECM sends a high signal to the solenoid in order to fill the clutch with oil quickly. Then, a reduced signal is sent to the solenoid in order to allow the clutch to engage smoothly.

Once the clutch engages, the machine ECM begins to increase the signal to solenoid (23) in order to further engage the clutch. When the signal to solenoid (23) increases, pin (22) moves to the right. Pin (22) pushes ball (9) toward orifice (21) and ball (9) restricts the flow of oil to tank passage (20). Oil pressure in chamber (10) will rise and valve spool (14) will move to the right. This causes the clutch pressure to increase.

Maximum Signal



Illustration 14g01338975
(9) Ball
(10) Chamber
(11) Orifice
(12) Test port
(13) Passage
(14) Valve spool
(15) Spring
(16) Chamber
(17) Passage
(18) Passage from the pump
(19) Passage to the clutch
(20) Passage to the tank
(21) Drain orifice
(22) Pin
(23) Solenoid
(AA) Pump oil
(BB) Return oil
(CC) Pilot oil

When the clutch is fully engaged, the machine ECM sends the maximum specified signal to solenoid (23) in order to keep the clutch fully engaged.

The signal that is sent to solenoid (23) moves pin (22) and ball (9) to the right. This further restricts the flow of return oil (BB) from passage (19) to tank passage (20). The pressure in chamber (5) increases and pump oil (AA) becomes pilot oil (CC). The valve spool (14) moves further to the right. The pump oil (AA) from pump passage (18) flows to passage (19) and the clutch will fully engage.

Once the clutch is fully engaged, the pump oil (AA) in chamber (10) and the combined pressure of oil in chamber (16) and spring (15) will equalize. This will cause valve spool (14) to move slightly to the left to a balanced position.

In the balanced position, the flow of oil from pump passage (18) to passage (19) maintains the desired clutch pressure. In the balanced position, pump oil (AA) flows to the clutch in order to compensate for internal leakage in the clutch.

Note: The modulating valves control the engaging and the disengaging of the clutches. This valve is not a simple on/off valve. The machine ECM varies the strength of the signal that is sent to the solenoid. The signal that is sent to the solenoid is programmed into the machine ECM.

Note: Since the main relief valve will control the maximum amount of clutch pressure for all of the modulating valves, the main relief pressure and the clutch pressure will be equal when the clutch is fully engaged.

Transmission Relief Valve



Illustration 15g01457446
(1) Transmission main relief valve

Transmission main relief valve (1) is located on the transmission case next to the modulating valves.

The transmission main relief valve (1) controls the maximum pressure of the clutches that are engaged. The transmission main relief valve controls the flow of oil that enters the modulating valves and the transmission main relief valve directs the remaining oil to the transmission for lubrication. The controlled flow provides a constant fill time for the clutches through the entire engine speed range.



Illustration 16g01457524
(2) Slug
(3) Spring
(4) Chamber
(5) Ball
(6) Orifice
(7) Chamber
(8) Spool
(9) Orifice
(10) Port to tank
(11) Pump port
(12) Port to transmission lubrication
(13) Spring
(AA) Pump oil
(BB) Tank oil
(CC) Lubrication oil

Pump oil (AA) flows into pump port (11). Pump oil (AA) flows into orifice (6) and the pump oil unseats ball (5). When ball (5) unseats, spring (3) compresses against slug (2). The pump oil flows past ball (5) and into chamber (4). The pressure in chamber (4) moves spool (8) to the right against spring (13). When spool (8) moves to the right, pump oil (AA) in pump port (11) flows past the spool and into the port to transmission lubrication (12) as lubricating oil (CC). Oil in chamber (7) is vented to the port to tank (10) as return oil (BB).

The pressure in pump port (11) will vary slightly with the demand from the clutches. When the pressure changes, spool (8) will move in order to maintain the required engagement pressure to the clutches. Spool (8) will direct the unneeded flow to the port to transmission lubrication (12).

When the pressure in pump port (11) decreases, spring (13) will move spool (8) to the left. When the spool moves to the left, the flow of oil into the port to transmission lubrication (12) will be blocked. As the pressure drops further, spring (3) will push ball (5) to the right. When ball (5) moves to the right, the flow of oil from pump port (11) into chamber (4) will be blocked. Oil in chamber (4) will drain back into pump port (11) through orifice (9) when ball (5) is moved to the right.

Transmission Power Flow

General Information



Illustration 17g01455438
Transmission hydraulic control
The following components are part of the transmission hydraulic system:
(1) Transmission relief valve
(2) Transmission (lubrication)
(3) Modulating valve for clutch 1 (Forward high)
(4) Transmission Electronic Control Module (ECM)
(5) Solenoid for clutch 2 (forward low)
(6) Modulating valve for clutch 2 (forward low)
(7) Clutch 2 (forward low)
(8) Solenoid for clutch 4 (second speed)
(9) Modulating valve for clutch 4 (second speed)
(10) Clutch 4 (second speed)
(11) Solenoid for clutch 6 (first speed)
(12) Modulating valve for clutch 6 (first speed)
(13) Clutch 6 (first speed)
(14) Modulating valve for clutch 8 (high range)
(15) Clutch 8 (high range)
(16) Solenoid for clutch 8 (high range)
(17) Modulating valve for clutch 5 (third speed)
(18) Modulating valve for clutch 7 (low range)
(19) Clutch 7 (low range)
(20) Solenoid for clutch 7 (low range)
(21) Magnetic screen
(22) Transmission sump
(23) Differential case
(24) Magnetic screen
(25) Pump
(25A) Transmission charging section
(25B) Transmission scavenge section
(26) Clutch 5 (third speed)
(27) Filter
(28) Solenoid for clutch 5 (third speed)
(29) Clutch 3 (reverse)
(30) Modulating valve for clutch 3 (reverse)
(31) Solenoid for clutch 3 (reverse)
(32) Clutch 1 (forward high)
(33) Transmission lubrication relief valve
(34) Solenoid for clutch 1 (forward high)
(35) Oil cooler
(36) Cooler bypass valve
(AA) Pressure oil
(BB) Tank oil
(CC) Lubrication oil
(DD) Moving parts

When the engine is started, transmission scavenge section (25B) of pump (25) pulls oil from the transmission sump (22) through magnetic screen (21) in order to direct the oil to the differential as lubricating oil (CC).

When the engine is started, transmission charging section (25A) of pump (25) pulls oil from differential case (23) through magnetic screen (24). Transmission charging section (25A) of pump (25) sends pressure oil (AA) through transmission oil filter (27). Pressure oil (AA) flows from the transmission oil filter (27) to the oil inlet in the transmission housing. The pressurized oil flows through an internal passage of transmission housing. The oil then flows to transmission relief valve (1). Transmission relief valve (1) controls the pressure of pump oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil through oil cooler (35) to the transmission (2) as lubrication oil (CC). After the oil cools, the oil flows through the lubrication system and to transmission sump (22). The pressurized oil flows out of transmission relief valve (1). The pressurized oil flows into the following modulating valves:

  • Modulating valve for clutch 1 (3)

  • Modulating valve for clutch 2 (6)

  • Modulating valve for clutch 3 (30)

  • Modulating valve for clutch 4 (9)

  • Modulating valve for clutch 5 (17)

  • Modulating valve for clutch 6 (12)

  • Modulating valve for clutch 7 (18)

  • Modulating valve for clutch 8 (14)

Transmission ECM (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM. Some of the inputs that are considered are machine speed, engine speed and operator inputs. A solenoid is located on each modulating valve. Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (5)

  • Clutch solenoid (8)

  • Clutch solenoid (11)

  • Clutch solenoid (16)

  • Clutch solenoid (20)

  • Clutch solenoid (28)

  • Clutch solenoid (31)

  • Clutch solenoid (34)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve. There is a modulating valve for each clutch. The modulating valves regulate pressure oil (AA) that is sent to the following clutches:

  • Clutch 2 (7)

  • Clutch 4 (10)

  • Clutch 6 (13)

  • Clutch 8 (15)

  • Clutch 7 (19)

  • Clutch 5 (26)

  • Clutch 3 (29)

  • Clutch 1 (32)

The modulating valve directs pressure oil (AA) to the clutch in order to engage the clutch. The solenoid controls the modulating valve spool. Transmission ECM (4) controls the solenoids. The oil in the clutches that are not engaged is sent back to transmission sump (22) and the oil becomes return oil (BB).

Table 1 gives the combination of the clutches that are engaged for each forward speed, neutral, and each reverse speed.

Table 1
  Clutch 1 (forward high)  Clutch 2 (forward low)  Clutch 3 (reverse)  Clutch 4 (second speed)  Clutch 5 (third speed)  Clutch 6 (first speed)  Clutch 7 (low range)  Clutch 8 (high range) 
First Speed Forward           
Second Speed Forward           
Third Speed Forward           
Fourth Speed Forward           
Fifth Speed Forward           
Sixth Speed Forward           
Seventh Speed Forward           
Eighth Speed Forward           
Neutral             
First Speed Reverse           
Second Speed Reverse           
Third Speed Reverse           
Fourth Speed Reverse           
Fifth Speed Reverse           
Sixth Speed Reverse           


Illustration 18g01455592
(7) Clutch 2 (forward low)
(10) Clutch 4 (second speed)
(13) Clutch 6 (first speed)
(15) Clutch 8 (high range)
(19) Clutch 7 (low range)
(26) Clutch 5 (third speed)
(29) Clutch 3 (reverse)
(32) Clutch 1 (forward high)
(37) Input shaft assembly
(38) Gear
(39) Gear
(40) Gear
(41) Wave spring
(42) Gear
(43) Gear
(44) Wave spring
(45) Gear
(46) Gear
(47) Wave spring
(48) Gear
(49) Yoke
(50) Parking brake assembly
(51) Gear
(52) Wave spring
(53) Wave spring
(54) Gear
(55) Rotor
(56) Shaft assembly
(57) Gear
(58) Gear
(59) Gear
(60) Shaft assembly
(61) Wave spring
(62) Gear
(63) Gear
(64) Shaft assembly
(65) Wave spring
(66) Wave spring
(67) Shaft assembly
(68) Gear

The countershaft transmission has eight forward speeds and six reverse speeds that are controlled by electronic clutch pressure control. The transmission has eight clutches that are engaged hydraulically. The clutches are disengaged by the following:

  • Wave Spring (41)

  • Wave Spring (44)

  • Wave Spring (47)

  • Wave Spring (52)

  • Wave Spring (53)

  • Wave Spring (61)

  • Wave Spring (65)

  • Wave Spring (66)

When a clutch is not engaged, the force of the wave spring retracts the piston to the disengaged position.

The transmission has five shafts: Input shaft assembly (37), and four clutch shaft assemblies. Input shaft assembly (37) is driven by the engine. Shaft assembly (67) contains clutch 1 (32) (forward high) and clutch 2 (7) (forward low). Shaft assembly (64) contains clutch 3 (29) (reverse) and clutch 4 (10) (second speed). Shaft assembly (60) contains clutch 5 (26) (third speed) and clutch 6 (13) (first speed). Shaft assembly (56) contains clutch 7 (19) (low range) and clutch 8 (15) (high range).

Parking brake assembly (50) is mounted to the transmission case.

Reference: Refer to the Power Train Systems Operation, "Parking Brake" for information about the operation of the parking brake (50).

Input shaft assembly (37) has one internal passage for lubrication and cooling of the bearings and gears. Shaft assembly (67), shaft assembly (64), shaft assembly (60) and shaft assembly (56) have four internal passages for hydraulic oil. Two passages supply the oil for the lubrication and cooling of the clutches, bearings and gears. The other two passages supply pressure oil for the engagement of the clutches on each shaft.

In order to transfer power through the transmission, a speed clutch, a direction clutch, and a range clutch must be engaged.

During cold weather and spikes in the oil pressure in the lubrication circuit, transmission lubrication relief valve (33) limits the lubrication oil pressure in order to protect the bearings and seals in the transmission.

First Speed Forward



Illustration 19g01455786
Transmission in FIRST SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (34)

  • Clutch solenoid (11)

  • Clutch solenoid (20)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 1 (3)

  • Modulating valve for clutch 6 (12)

  • Modulating valve for clutch 7 (18)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in FIRST SPEED FORWARD, the solenoid on modulating valve (3) for clutch 1 (32) (forward high), the solenoid on modulating valve (12) for clutch 6 (13) (first speed), and the solenoid on modulating valve (18) for clutch 7 (19) (low range) are energized.

When solenoid (34) on modulating valve (3) is energized, valve (3) directs pump oil (AA) to clutch 1 (32) in order to engage the clutch.

When solenoid (11) on modulating valve (12) is energized, valve (12) directs pump oil (AA) to clutch 6 (13) in order to engage the clutch.

When solenoid (20) on modulating valve (18) is energized, valve (18) directs pump oil (AA) to clutch 7 (19) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 20g01455826
Transmission in FIRST SPEED FORWARD

When the transmission is in FIRST SPEED FORWARD, clutch 1 (32), clutch 6 (13), and clutch 7 (19) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (38) is splined to input shaft assembly (37). When clutch 1 (32) is engaged, torque is transferred from input shaft assembly (37) through gear (38) and gear (68) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 6 (13) is engaged, torque is transferred from shaft assembly (64) through gear (63) and gear (59) in order to turn shaft assembly (60).

When clutch 7 (19) is engaged, torque is transferred from shaft assembly (60) through gear (46) and gear (51) in order to turn shaft assembly (56).

Second Speed Forward



Illustration 21g01455888
Transmission in SECOND SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (5)

  • Clutch solenoid (8)

  • Clutch solenoid (20)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 2 (6)

  • Modulating valve for clutch 4 (9)

  • Modulating valve for clutch 7 (18)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in SECOND SPEED FORWARD, the solenoid on modulating valve (6) for clutch 2 (7) (forward low), the solenoid on modulating valve (9) for clutch 4 (10) (second speed), and the solenoid on modulating valve (18) for clutch 7 (19) (low range) are energized.

When solenoid (5) on modulating valve (6) is energized, valve (6) directs pump oil (AA) to clutch 2 (7) in order to engage the clutch.

When solenoid (8) on modulating valve (9) is energized, valve (9) directs pump oil (AA) to clutch 4 (10) in order to engage the clutch.

When solenoid (20) on modulating valve (18) is energized, valve (18) directs pump oil (AA) to clutch 7 (19) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil.

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 22g01455919
Transmission in SECOND SPEED FORWARD

When the transmission is in SECOND SPEED FORWARD, clutch 2 (7), clutch 4 (10), and clutch 7 (19) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 2 (7) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (42) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 4 (10) is engaged, torque is transferred from shaft assembly (64) through gear (62) and gear (57) in order to turn shaft assembly (60).

When clutch 7 (19) is engaged, torque is transferred from shaft assembly (60) through gear (46) and gear (51) in order to turn shaft assembly (56).

Third Speed Forward



Illustration 23g01455959
Transmission in THIRD SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (5)

  • Clutch solenoid (28)

  • Clutch solenoid (20)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 2 (6)

  • Modulating valve for clutch 5 (17)

  • Modulating valve for clutch 7 (18)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in THIRD SPEED FORWARD, the solenoid on modulating valve (6) for clutch 2 (7) (forward low), the solenoid on modulating valve (17) for clutch 5 (26) (third speed), and the solenoid on modulating valve (18) for clutch 7 (19) (low range) are energized.

When solenoid (5) on modulating valve (6) is energized, valve (6) directs pump oil (AA) to clutch 2 (7) in order to engage the clutch.

When solenoid (28) on modulating valve (17) is energized, valve (17) directs pump oil (AA) to clutch 5 (26) in order to engage the clutch.

When solenoid (20) on modulating valve (18) is energized, valve (18) directs pump oil (AA) to clutch 7 (19) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 24g01455967
Transmission in THIRD SPEED FORWARD

When the transmission is in THIRD SPEED FORWARD, clutch 2 (7), clutch 5 (26), and clutch 7 (19) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 2 (7) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (42) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 5 (26) is engaged, torque is transferred from shaft assembly (64) through gear (45) and gear (48) in order to turn shaft assembly (60).

When clutch 7 (19) is engaged, torque is transferred from shaft assembly (60) through gear (46) and gear (51) in order to turn shaft assembly (56).

Fourth Speed Forward



Illustration 25g01456004
Transmission in FOURTH SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (34)

  • Clutch solenoid (28)

  • Clutch solenoid (20)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 1 (3)

  • Modulating valve for clutch 5 (17)

  • Modulating valve for clutch 7 (18)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in FOURTH SPEED FORWARD, the solenoid on modulating valve (3) for clutch 1 (32) (forward high), the solenoid on modulating valve (17) for clutch 5 (26) (third speed), and the solenoid on modulating valve (18) for clutch 7 (19) (low range) are energized.

When solenoid (34) on modulating valve (3) is energized, valve (3) directs pump oil (AA) to clutch 1 (32) in order to engage the clutch.

When solenoid (28) on modulating valve (17) is energized, valve (17) directs pump oil (AA) to clutch 5 (26) in order to engage the clutch.

When solenoid (20) on modulating valve (18) is energized, valve (18) directs pump oil (AA) to clutch 7 (19) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 26g01456007
Transmission in FOURTH SPEED FORWARD

When the transmission is in FOURTH SPEED FORWARD, clutch 1 (32), clutch 5 (26), and clutch 7 (19) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (38) is splined to input shaft assembly (37). When clutch 1 (32) is engaged, torque is transferred from input shaft assembly (37) through gear (38) and gear (68) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 5 (26) is engaged, torque is transferred from shaft assembly (64) through gear (45) and gear (48) in order to turn shaft assembly (60).

When clutch 7 (19) is engaged, torque is transferred from shaft assembly (60) through gear (46) and gear (51) in order to turn shaft assembly (56).

Fifth Speed Forward



Illustration 27g01456206
Transmission in FIFTH SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (34)

  • Clutch solenoid (11)

  • Clutch solenoid (16)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 1 (3)

  • Modulating valve for clutch 6 (12)

  • Modulating valve for clutch 8 (14)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in FIFTH SPEED FORWARD, the solenoid on modulating valve (3) for clutch 1 (32) (forward high), the solenoid on modulating valve (12) for clutch 6 (13) (first speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (34) on modulating valve (3) is energized, valve (3) directs pump oil (AA) to clutch 1 (32) in order to engage the clutch.

When solenoid (11) on modulating valve (12) is energized, valve (12) directs pump oil (AA) to clutch 6 (13) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 28g01456222
Transmission in FIFTH SPEED FORWARD

When the transmission is in FIFTH SPEED FORWARD, clutch 1 (32), clutch 6 (13), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (38) is splined to input shaft assembly (37). When clutch 1 (32) is engaged, torque is transferred from input shaft assembly (37) through gear (38) and gear (68) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 6 (13) is engaged, torque is transferred from shaft assembly (64) through gear (63) and gear (59) in order to turn shaft assembly (60).

When clutch 8 (15) is engaged, torque is transferred from shaft assembly (60) through gear (58) and gear (54) in order to turn shaft assembly (56).

Sixth Speed Forward



Illustration 29g01456262
Transmission in SIXTH SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (5)

  • Clutch solenoid (8)

  • Clutch solenoid (16)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 2 (6)

  • Modulating valve for clutch 4 (9)

  • Modulating valve for clutch 8 (14)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in SIXTH SPEED FORWARD, the solenoid on modulating valve (6) for clutch 2 (7) (forward low), the solenoid on modulating valve (9) for clutch 4 (10) (second speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (5) on modulating valve (6) is energized, valve (6) directs pump oil (AA) to clutch 2 (7) in order to engage the clutch.

When solenoid (8) on modulating valve (9) is energized, valve (9) directs pump oil (AA) to clutch 4 (10) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 30g01456265
Transmission in SIXTH SPEED FORWARD

When the transmission is in SIXTH SPEED FORWARD, clutch 2 (7), clutch 4 (10), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 2 (7) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (42) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 4 (10) is engaged, torque is transferred from shaft assembly (64) through gear (62) and gear (57) in order to turn shaft assembly (60).

When clutch 8 (15) is engaged, torque is transferred from shaft assembly (60) through gear (58) and gear (54) in order to turn shaft assembly (56).

Seventh Speed Forward



Illustration 31g01456291
Transmission in SEVENTH SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (34)

  • Clutch solenoid (8)

  • Clutch solenoid (16)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 1 (3)

  • Modulating valve for clutch 4 (9)

  • Modulating valve for clutch 8 (14)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in SEVENTH SPEED FORWARD, the solenoid on modulating valve (3) for clutch 1 (32) (forward high), the solenoid on modulating valve (9) for clutch 4 (10) (second speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (34) on modulating valve (3) is energized, valve (3) directs pump oil (AA) to clutch 1 (32) in order to engage the clutch.

When solenoid (8) on modulating valve (9) is energized, valve (9) directs pump oil (AA) to clutch 4 (10) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 32g01456346
Transmission in SEVENTH SPEED FORWARD

When the transmission is in SEVENTH SPEED FORWARD, clutch 1 (32), clutch 4 (10), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (38) is splined to input shaft assembly (37). When clutch 1 (32) is engaged, torque is transferred from input shaft assembly (37) through gear (38) and gear (68) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 4 (10) is engaged, torque is transferred from shaft assembly (64) through gear (62) and gear (57) in order to turn shaft assembly (60).

When clutch 8 (15) is engaged, torque is transferred from shaft assembly (60) through gear (58) and gear (54) in order to turn shaft assembly (56).

Eighth Speed Forward



Illustration 33g01456414
Transmission in EIGHTH SPEED FORWARD

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (34)

  • Clutch solenoid (28)

  • Clutch solenoid (16)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 1 (3)

  • Modulating valve for clutch 5 (17)

  • Modulating valve for clutch 8 (14)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in EIGHTH SPEED FORWARD, the solenoid on modulating valve (3) for clutch 1 (32) (forward high), the solenoid on modulating valve (17) for clutch 5 (26) (third speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (34) on modulating valve (3) is energized, valve (3) directs pump oil (AA) to clutch 1 (32) in order to engage the clutch.

When solenoid (28) on modulating valve (17) is energized, valve (17) directs pump oil (AA) to clutch 5 (26) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 34g01456422
Transmission in EIGHTH SPEED FORWARD

When the transmission is in EIGHTH SPEED FORWARD, clutch 1 (32), clutch 5 (26), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (38) is splined to input shaft assembly (37). When clutch 1 (32) is engaged, torque is transferred from input shaft assembly (37) through gear (38) and gear (68) in order to turn shaft assembly (67).

Gear (39) is part of shaft assembly (67) which causes gear (39) to turn. Torque is transferred from shaft assembly (67) through gear (39) and gear (45) to shaft assembly (64).

When clutch 5 (26) is engaged, torque is transferred from shaft assembly (64) through gear (45) and gear (48) in order to turn shaft assembly (60).

When clutch 8 (15) is engaged, torque is transferred from shaft assembly (60) through gear (58) and gear (54) in order to turn shaft assembly (56).

Neutral



Illustration 35g01456575
Transmission in NEUTRAL

When the transmission is in NEUTRAL, the solenoid on modulating valve (17) for clutch 5 (26) (Third speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (28) on modulating valve (17) is energized, valve (17) directs pump oil (AA) to clutch 5 (26) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 36g01456581
Transmission in NEUTRAL

When the transmission is in NEUTRAL, clutch 5 (26), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (38) is splined to input shaft assembly (37) and gear (40) is splined to input shaft assembly (37). Because clutch 1 (32), clutch 2 (7), or clutch 3 (29) is not engaged, power is not transferred from the input shaft through the transmission. Clutch 5 (26) and clutch 8 (15) are engaged when the transmission is in NEUTRAL.

First Speed Reverse



Illustration 37g01456588
Transmission in FIRST SPEED REVERSE

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (31)

  • Clutch solenoid (11)

  • Clutch solenoid (20)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 3 (30)

  • Modulating valve for clutch 6 (12)

  • Modulating valve for clutch 7 (18)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in FIRST SPEED REVERSE, the solenoid on modulating valve (30) for clutch 3 (29) (reverse), the solenoid on modulating valve (12) for clutch 6 (13) (first speed), and the solenoid on modulating valve (18) for clutch 7 (19) (low range) are energized.

When solenoid (31) on modulating valve (30) is energized, valve (30) directs pump oil (AA) to clutch 3 (29) in order to engage the clutch.

When solenoid (11) on modulating valve (12) is energized, valve (12) directs pump oil (AA) to clutch 6 (13) in order to engage the clutch.

When solenoid (20) on modulating valve (18) is energized, valve (18) directs pump oil (AA) to clutch 7 (19) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 38g01456601
Transmission in FIRST SPEED REVERSE

When the transmission is in FIRST SPEED REVERSE, clutch 3 (29), clutch 6 (13), and clutch 7 (19) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 3 (29) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (43) in order to turn shaft assembly (64).

When clutch 6 (13) is engaged, torque is transferred from shaft assembly (64) through gear (63) and gear (59) in order to turn shaft assembly (60).

When clutch 7 (19) is engaged, torque is transferred from shaft assembly (60) through gear (46) and gear (51) in order to turn shaft assembly (56).

Second Speed Reverse



Illustration 39g01456625
Transmission in SECOND SPEED REVERSE

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (31)

  • Clutch solenoid (8)

  • Clutch solenoid (20)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 3 (30)

  • Modulating valve for clutch 4 (9)

  • Modulating valve for clutch 7 (18)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in SECOND SPEED REVERSE, the solenoid on modulating valve (30) for clutch 3 (29) (reverse), the solenoid on modulating valve (9) for clutch 4 (10) (second speed), and the solenoid on modulating valve (18) for clutch 7 (19) (low range) are energized.

When solenoid (31) on modulating valve (30) is energized, valve (30) directs pump oil (AA) to clutch 3 (29) in order to engage the clutch.

When solenoid (8) on modulating valve (9) is energized, valve (9) directs pump oil (AA) to clutch 4 (10) in order to engage the clutch.

When solenoid (20) on modulating valve (18) is energized, valve (18) directs pump oil (AA) to clutch 7 (19) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 40g01456675
Transmission in SECOND SPEED REVERSE

When the transmission is in SECOND SPEED REVERSE, clutch 3 (29), clutch 4 (10), and clutch 7 (19) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 3 (29) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (43) in order to turn shaft assembly (64).

When clutch 4 (10) is engaged, torque is transferred from shaft assembly (64) through gear (62) and gear (57) in order to turn shaft assembly (60).

When clutch 7 (19) is engaged, torque is transferred from shaft assembly (60) through gear (46) and gear (51) in order to turn shaft assembly (56).

Third Speed Reverse



Illustration 41g01456703
Transmission in THIRD SPEED REVERSE

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (31)

  • Clutch solenoid (28)

  • Clutch solenoid (20)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 3 (30)

  • Modulating valve for clutch 5 (17)

  • Modulating valve for clutch 7 (18)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in THIRD SPEED REVERSE, the solenoid on modulating valve (30) for clutch 3 (29) (reverse), the solenoid on modulating valve (17) for clutch 5 (26) (third speed), and the solenoid on modulating valve (18) for clutch 7 (19) (low range) are energized.

When solenoid (31) on modulating valve (30) is energized, valve (30) directs pump oil (AA) to clutch 3 (29) in order to engage the clutch.

When solenoid (28) on modulating valve (17) is energized, valve (17) directs pump oil (AA) to clutch 5 (26) in order to engage the clutch.

When solenoid (20) on modulating valve (18) is energized, valve (18) directs pump oil (AA) to clutch 7 (19) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to the sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 42g01456717
Transmission in THIRD SPEED REVERSE

When the transmission is in THIRD SPEED REVERSE, clutch 3 (29), clutch 5 (26), and clutch 7 (19) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 3 (29) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (43) in order to turn shaft assembly (64).

When clutch 5 (26) is engaged, torque is transferred from shaft assembly (64) through gear (45) and gear (48) in order to turn shaft assembly (60).

When clutch 7 (19) is engaged, torque is transferred from shaft assembly (60) through gear (46) and gear (51) in order to turn shaft assembly (56).

Fourth Speed Reverse



Illustration 43g01456757
Transmission in FOURTH SPEED REVERSE

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (31)

  • Clutch solenoid (11)

  • Clutch solenoid (16)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 3 (30)

  • Modulating valve for clutch 6 (12)

  • Modulating valve for clutch 8 (14)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in FOURTH SPEED REVERSE, the solenoid on modulating valve (30) for clutch 3 (29) (reverse), the solenoid on modulating valve (12) for clutch 6 (13) (first speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (31) on modulating valve (30) is energized, valve (30) directs pump oil (AA) to clutch 3 (29) in order to engage the clutch.

When solenoid (11) on modulating valve (12) is energized, valve (12) directs pump oil (AA) to clutch 6 (13) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 44g01456769
Transmission in FOURTH SPEED REVERSE

When the transmission is in FOURTH SPEED REVERSE, clutch 3 (29), clutch 6 (13), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 3 (29) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (43) in order to turn shaft assembly (64).

When clutch 6 (13) is engaged, torque is transferred from shaft assembly (64) through gear (63) and gear (59) in order to turn shaft assembly (60).

When clutch 8 (15) is engaged, torque is transferred from shaft assembly (60) through gear (58) and gear (54) in order to turn shaft assembly (56).

Fifth Speed Reverse



Illustration 45g01456790
Transmission in FIFTH SPEED REVERSE

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (31)

  • Clutch solenoid (8)

  • Clutch solenoid (16)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 3 (30)

  • Modulating valve for clutch 4 (9)

  • Modulating valve for clutch 8 (14)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in FIFTH SPEED REVERSE, the solenoid on modulating valve (30) for clutch 3 (29) (reverse), the solenoid on modulating valve (9) for clutch 4 (10) (second speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (31) on modulating valve (30) is energized, valve (30) directs pump oil (AA) to clutch 3 (29) in order to engage the clutch.

When solenoid (8) on modulating valve (9) is energized, valve (9) directs pump oil (AA) to clutch 4 (10) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 46g01456810
Transmission in FIFTH SPEED REVERSE

When the transmission is in FIFTH SPEED REVERSE, clutch 3 (29), clutch 4 (10), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 3 (29) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (43) in order to turn shaft assembly (64).

When clutch 4 (10) is engaged, torque is transferred from shaft assembly (64) through gear (62) and gear (57) in order to turn shaft assembly (60).

When clutch 8 (15) is engaged, torque is transferred from shaft assembly (60) through gear (58) and gear (54) in order to turn shaft assembly (56).

Sixth Speed Reverse



Illustration 47g01456829
Transmission in SIXTH SPEED REVERSE

The transmission Electronic Control Module (ECM) (4) determines the proper clutches that need to be engaged. The proper clutch engagement is based on the inputs to the transmission ECM (4). Some of the inputs that are considered are machine speed, engine speed, and operator inputs.

Transmission ECM (4) modulates the electrical current that is sent to the following solenoids:

  • Clutch solenoid (31)

  • Clutch solenoid (28)

  • Clutch solenoid (16)

The clutch solenoids are located on the following valves:

  • Modulating valve for clutch 3 (30)

  • Modulating valve for clutch 5 (17)

  • Modulating valve for clutch 8 (14)

Modulating the current to the clutch solenoid controls the clutch pressure by shifting the spool in the modulating valve.

When the transmission is in SIXTH SPEED REVERSE, the solenoid on modulating valve (30) for clutch 3 (29) (reverse), the solenoid on modulating valve (17) for clutch 5 (26) (third speed), and the solenoid on modulating valve (14) for clutch 8 (15) (high range) are energized.

When solenoid (31) on modulating valve (30) is energized, valve (30) directs pump oil (AA) to clutch 3 (29) in order to engage the clutch.

When solenoid (28) on modulating valve (17) is energized, valve (17) directs pump oil (AA) to clutch 5 (26) in order to engage the clutch.

When solenoid (16) on modulating valve (14) is energized, valve (14) directs pump oil (AA) to clutch 8 (15) in order to engage the clutch.

The oil in the clutches that are not engaged is sent back to sump (22) and the oil becomes return oil (BB).

Transmission relief valve (1) controls the pressure of pressure oil (AA) that is supplied to the modulating valves. Transmission relief valve (1) directs the unneeded pump oil to oil cooler (35) as lubrication oil (CC) for transmission lubrication (2). The transmission is lubricated and the oil drains to sump (22). Transmission lubrication relief valve (33) limits the pressure in the lubrication circuit in order to protect the seals and bearings in the transmission. Unwanted oil returns to transmission sump (22) as return oil (BB).



Illustration 48g01456837
Transmission in SIXTH SPEED REVERSE

When the transmission is in SIXTH SPEED REVERSE, clutch 3 (29), clutch 5 (26), and clutch 8 (15) are engaged.

Torque from the engine is transferred to input shaft assembly (37). Gear (40) is splined to input shaft assembly (37). When clutch 3 (29) is engaged, torque is transferred from input shaft assembly (37) through gear (40) and gear (43) in order to turn shaft assembly (64).

When clutch 5 (26) is engaged, torque is transferred from shaft assembly (64) through gear (45) and gear (48) in order to turn shaft assembly (60).

When clutch 8 (15) is engaged, torque is transferred from shaft assembly (60) through gear (58) and gear (54) in order to turn shaft assembly (56).

Speed Sensors

The transmission has six speed sensors, four input and two output. Refer to the following illustration for wiring information.



Illustration 49g03578443
Transmission ECM and transmission speed sensors
(1) Input speed sensor
(2) Intermediate speed sensor
(3) Intermediate speed sensor
(4) Transmission speed sensor
(5) Output speed sensor
(6) Output speed sensor

Transmission Controls

The upshift and downshift controls control the active gears in the transmission. The upshift and downshift controls are located on the left hand joystick. The transmission modulation pedal will allow the machine to creep at low speeds. The transmission auto/manual function puts the transmission in automatic or manual mode. The auto/manual switch is located on the right hand control panel. All of these function are outlined in the following illustration.



Illustration 50g03579236
(1) Transmission ECM J1
(2) Transmission ECM J2
(3) Left hand joystick J2
(4) Transmission auto/manual toggle switch
(5) Inching pedal position sensor
(6) Inching pedal position switch

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