SEAL GROUP 8S5656 - Caterpillar

Introduction
The power train is made up of the following three basic systems:
Power train electronic control module
Torque converter
Transmission planetary and transmissionThe three basic systems have a hydraulic connection, an electrical connection, a magnetic connection, or a mechanical connection. Power is supplied from the engine to the torque converter and goes to the transmission. If the transmission is in gear, power flows from the transmission to the output shaft. The operation of the power train begins at the power train Electronic Control Module (ECM). The power train ECM receives information about the selected speed of operation through the shifter in the electrical system. The power train ECM uses information from several sensors in the electrical system to control the torque converter and the transmission hydraulic system by energizing the appropriate solenoids.The rotating housing of the torque converter is fastened directly to the engine flywheel. The torque converter has a lockup clutch for direct drive and a one-way clutch for the torque converter drive. During torque converter drive, power is transmitted through the torque converter hydraulically to the transmission. During direct drive, there is a direct connection between the engine flywheel and the transmission.The power train ECM will hydraulically activate the lockup clutch solenoid for direct drive operation. The full power from the engine flywheel is transmitted through the torque converter when the torque converter is in direct drive. The lockup clutch becomes a direct connection between the rotating housing and the output shaft of the torque converter. The output shaft of the torque converter is connected to the planetary. The power train ECM will activate the appropriate Electronic Clutch Pressure Control (ECPC) valves in order to activate the correct transmission clutches when shifts are needed. The transmission clutches mechanically connect the transmission input shaft to the output shaft. Different combinations of clutches result in different gears and the transmission output shaft speeds. Refer to Table 1 for combinations of different gears and transmission output shaft speeds.
Table 1
CX31-P600 Transmission Clutch Assignments
Operation Gear Ratios Clutches Transmission Output Speed at 800 RPM Input with LUC Engaged (RPM) Transmission Output Speed at 1200 RPM Input with LUC Engaged (RPM)
1 2 3 4 5
Neutral O - -
1 Forward 4.40 O O 182 500
2 Forward 2.33 O O 343 943
3 Forward 1.53 O O 552 1435
4 Forward 1.00 O O 800 2200
5 Forward 0.72 O O 1114 3062
6 Forward 0.61 O O 1315 3617
Reverse -3.97 O O 202 554
Park O O - -
Warm-up O O O - - When the output shaft of the transmission is rotating, the speed sensors send an AC frequency signal (HZ) that matches the number of gear teeth that are passing the sensor per second to the ECM. The ECM compares the frequency from the speed sensor (HZ) to the number of pulses per revolution in order to