GEAR (58 TEETH) 7K4458 - Caterpillar

Refer to Systems Operation, Testing and Adjusting, "General Troubleshooting Information" before you perform any Testing and Adjusting or troubleshooting.Prior to starting with checks on the modulating valves, use Caterpillar ET in order to diagnose any fault codes that may be present. Refer to Systems Operation, Troubleshooting, Testing and Adjusting, KENR5099, "Power Train Electronic Control System".After checking for fault codes, run a calibration of the transmission. Refer to Systems Operation, Testing and Adjusting, "Transmission - Calibrate".Testing The Modulating Valves
Illustration 1 g02024413
Modulating Valves (Electronic Clutch Pressure Control)
(1) Modulating valve 1
(2) Modulating valve 2
(3) Modulating valve 3
(4) Modulating valve 4
(5) Modulating valve 5
(6) Lockup clutch modulating valve
Table 1
CX31 SPEED SELECTION
SPEED ENGAGED CLUTCHES
(= ENERGIZED VALVES)
Reverse 3 and 5
Neutral 5
First Gear Forward 1 and 5
Second Gear Forward 1 and 4
Third Gear Forward 1 and 3
Fourth Gear Forward 1 and 2
Fifth Gear Forward 2 and 3
Sixth Gear Forward 2 and 4 The pressure test points for the transmission clutches are installed in the modulating valves (electronic clutch pressure control). The modulating valves (electronic clutch pressure control) are located on the lower left side of the transmission.With a stationary truck, the pressure of the oil in the transmission clutches can only be tested on the valve that is engaged when the transmission is in neutral. Refer to Systems Operation, Testing and Adjusting, "Power Train Pressures".With the transmission in neutral, if the pressure in the engaged valve is correct, the oil supply to the modulating valves (electronic clutch pressure control) is sufficient.The pressures for some of the remaining clutches can be measured on a stationary truck. The pressures for some of the remaining clutches must be measured on a moving truck. Refer to Systems Operation, Testing and Adjusting, "Power Train Pressures" for the correct procedure to test the pressures in the transmission clutches.If the transmission is observed to slip in one gear, a transmission clutch may not be functioning correctly. Use Table 1 in order to determine the transmission clutch that may not be functioning correctly.