CYLINDER 1080801 - Caterpillar

Transmission Components
Illustration 1 g02574956
(1) Filter inlet pressure test port (scheduled oil sampling port) (2) Filter outlet pressure test port (3) Two M16x2 rear mounting and lifting points (4) Torque converter output speed sensor (5) Conventional ten bolt PTO at 1:00 o'clock position (6) No. 1 SAE J615 side mounting bolt pad spacing six M16x2 threads (7) Oil filler and dipstick location (8) Standard 120 mm (4.72 inch) deep sump oil pan (9) Four M16x2 threaded mounts (10) Transmission output speed sensor (11) Optional 1085 N m (800 lb ft) rear PTO capability (12) Rear magnetic drain plug (1 1/16 - 12 - 2A O-ring face seal) (13) SAE J1926 #4 auxiliary PTO lube (14) Output yoke (15) Transmission mounted cartridge type oil filter
Illustration 2 g02575236
(16) Input shaft from engine flywheel (17) Flex plate (18) Flywheel gear (19) Torque converter housing (20) Input speed sensor to planetary transmission from engine (21) Breather (22) Receptacle (23) Electronic control module (ECM) (24) Temperature sensor (pump outlet and filter inlet) (25) Modulating valve (26) Guard (ECPC valve guard) (27) Filter outlet pressure port (PTO lube port) (28) Conventional ten bolt PTO at 8 o'clock position (29) Oil flow from cooler (30) Lube oil pressure tap (31) Oil flow to cooler (32) Torque converter out pressure tap (33) Oil cooler inlet pressure tap (34) Temperature sensor to cooler (35) Torque converter outlet relief valve (36) Main hydraulic relief valve (37) Filter bypass valve
Illustration 3 g02580124
(38) Retarders add 104 mm (4.09 inch) to the length of the CX31 Transmission. (39) Retarder activation solenoid (40) Retarder activation pressure port (41) SAE J1926 #24 inlet from cooler (42) SAE J1926 #24 outlet to coolerControl of the transmission planetary is achieved by hydraulically actuated clutches that hold selected components of the planetary group stationary. This design allows drive through the transmission. Each combination of clutches produces a different gear ratio and speed.Transmission Hydraulic System
Illustration 4 g01266253
(45) Pressurized oil (46) Solenoid (ECPC modulating valve) (47) Modulating valveOil is supplied by the transmission pump through a filter. Oil (45) is available to each modulating valve (47) .Control of the transmission planetary is achieved by hydraulically actuated clutches. These clutches hold selected components of the planetary group stationary in order to allow drive through the transmission.Shifting of the transmission is controlled by the electronic control module (ECM). The ECM acts in response to various inputs.Inputs to the ECM module include the following information.
Selected Gear
Engine Speed
Output Speed
High Gear LimitThe control of the transmission also accounts for factors such as the temperature of the transmission oil.Shifting of the transmission gears involves the release of one clutch and the subsequent engagement of the next clutch.Each clutch is engaged by hydraulic oil pressure that is supplied by the modulating valves. The modulating valves are controlled by pulse width modulated signals (PWM). The signals are sent by the ECM to individual solenoid (46) on each modulating valve (47) .For details of the operation of the modulating valves, refer to Systems Operation, Testing and Adjusting, "Modulating Valves (Electronic Clutch Pressure