740 ARTIICULATED TRUCK POWER TRAIN

7 4 0 A R T I C U L AT E D T R U C K POWER TRAIN

740

©2001 Caterpillar Inc.

740 TRANSMISSION HYDRAULIC SYSTEM NEUTRAL

DOWNSHIFT PRESSURE

UPSHIFT PRESSURE

A DOWNSHIFT UPSHIFT SOLENOID SOLENOID

ROTARY ACTUATOR

FILTER PUMP PRESSURE

E

ON

B NEUTRALIZER VALVE

PILOT OIL PRESSURE

PRIORITY REDUCTION VALVE

F

ROTARY SELECTOR SPOOL

C

TRANSMISSION PUMP

G D RELIEF VALVE

H

T/C LOCKUP SOLENOID

SELECTOR VALVE GROUP

TORQUE CONVERTER SUMP

LUBE RELIEF VALVE

LUBE PRESSURE

PRESSURE CONTROL GROUP

OUTPUT TRANSFER GEAR HYDRAULIC CIRCUIT DIFFERENTIAL LOCKS RELEASED SOLENOID VALVE SOLENOID VALVE

INTERAXLE DIFFERENTIAL

PRIORITY VALVE

CHARGE PUMP

MAGNETIC SCREEN

TRANSFER GEAR

RELIEF VALVE

AXLE

AXLE

AXLE

OUTPUT TRANSFER GEAR HYDRAULIC CIRCUIT INTERAXLE LOCK ENGAGED SOLENOID VALVE SOLENOID VALVE

INTERAXLE DIFFERENTIAL

PRIORITY VALVE

CHARGE PUMP

MAGNETIC SCREEN

TRANSFER GEAR

RELIEF VALVE

AXLE

AXLE

AXLE

OUTPUT TRANSFER GEAR HYDRAULIC CIRCUIT INTERAXLE AND DIFFERENTIAL LOCKS ENGAGED SOLENOID VALVE SOLENOID VALVE

INTERAXLE DIFFERENTIAL

PRIORITY VALVE

CHARGE PUMP

MAGNETIC SCREEN

TRANSFER GEAR

RELIEF VALVE

AXLE

AXLE

AXLE

740 TRANSMISSION HYDRAULIC SYSTEM NEUTRAL

DOWNSHIFT PRESSURE

UPSHIFT PRESSURE

A DOWNSHIFT UPSHIFT SOLENOID SOLENOID

ROTARY ACTUATOR

FILTER PUMP PRESSURE

E

ON

B NEUTRALIZER VALVE

PILOT OIL PRESSURE

PRIORITY REDUCTION VALVE

F

ROTARY SELECTOR SPOOL

C

TRANSMISSION PUMP

G D

RELIEF VALVE

H

T/C LOCKUP SOLENOID

SELECTOR VALVE GROUP

TORQUE CONVERTER SUMP

LUBE RELIEF VALVE

LUBE PRESSURE

PRESSURE CONTROL GROUP

A B J C

I D

H G F

1

GND VERIFY

2

GEAR 5

3

GEAR 4

4

+ BATT

5 6 7 8 9 10

GEAR 3 GEAR 2 GEAR 1 GROUND

E

TRANSMISSION GEAR POSITION SWITCH 10 9 8 7 6

4 3 2 1

FROM SELECTOR AND PRESSURE CONTROL VALVE

PUMP PASSAGE

PRESSURE CONTROL VALVE

A LOAD PISTON BODY

E B

TRANSMISSION PRESSURE CONTROL VALVE

F

NEUTRAL C FROM SELECTOR  AND PRESSURE CONTROL VALVE

G

D

H MODULATION

FROM SELECTOR

MODULATION REDUCTION VALVES

TRANSMISSION PLANETARY VALVE STATION CLUTCH FILLING TO TANK

TO TANK FROM SELECTION

PISTON PASSAGE

MODULATION   SELECTOR REDUCTION VALVE PISTON

LOAD PISTON ORIFICE

LOAD PISTON

TRANSMISSION PLANETARY VALVE STATION CLUTCH ENGAGED

TRANSMISSION PLANETARY VALVE STATION CLUTCH DECAY

DECAY ORIFICE TO TRANSMISSION

TORQUE CONVERTER LOCKUP VALVE STATION

TO TANK

LOAD PISTON ORIFICE

FROM SELECTOR AND PRESSURE CONTROL VALVE

LOAD PISTON

SELECTOR PISTON

FROM T/C LOCKUP SOLENOID

BALL CHECK VALVE

MODULATION REDUCTION VALVE

740 TRANSMISSION SELECTOR VALVE GROUP NEUTRAL

NEUTRALIZER VALVE PRIORITY REDUCTION VALVE PILOT OIL PRESSURE TAP

FROM TRANSMISSION PUMP

ROTARY SELECTOR SPOOL

SCREEN

TO TRANSMISSION PRESSURE CONTROL VALVE

RELIEF VALVE

LUBE RELIEF VALVE

LUBRICATION

TO TRANSMISSION PRESSURE