Diagnostic Test
- CHECK FOR RELATED DTCS
- With the scan tool, check for other transmission DTCs.
Are there any Transmission solenoid, line pressure, speed sensor, and/or loss of prime DTCs present?
Yes
- Perform the test for P0944-LOSS OF PRIME first if it is present. Refer to Diagnosis and Testing .
No
- Go To 2.
- With the scan tool, check for other transmission DTCs.
- CHECK IF DTC IS CURRENT NOTE:
Make sure to record all Event Data stored in the scan tool for future reference in this test procedure.
- With the scan tool, perform the Reverse Gear Clutch test. Follow the instructions on the scan tool.
- Increase the throttle angle, TPS degree, to 30°, for no more than a few seconds.CAUTION:
Do not overheat the transmission.
Did the clutch test pass, input speed remain at zero?
Yes
- Go To 3.
No
- Go To 4.
- CHECK THE EVENT DATA
- POSSIBLE INTERNAL TRANSMISSION CAUSES
- Remove the Transmission Oil Pan and Valve Body and check the following in accordance with the Service Information:
- Clutch or metal debris in the pan
- L/R clutch tower seal on the main valve body or cuts and the L/R accumulator piston and seals.
- Air check the Reverse and L/R Hydraulic Clutch circuits (in the case) for excessive air leakage.
NOTE:Both Hydraulic Clutch circuits contain a small bleed orifice , a small amount of air leakage is normal. The Reverse hydraulic clutch circuit bleed orifice connects to the OD hydraulic clutch cavity. A small amount of air leakage into the OD hydraulic clutch circuit is considered normal.
Were there any problems found?
Yes
- Repair as necessary. If clutch debris is present, remove the transmission and inspect the Reverse and L/R clutches, and inspect the Transmission Oil Pump and Main Regulator Valve for damage or sticking in its bore.NOTE:
If the L/R clutch has failed but no obvious cause is found (such as a cut piston seal, cut tower seal, stuck regulator valve or any other items listed above) replace the Transmission Solenoid/TRS Assembly in addition to any necessary internal repairs.
- Perform the appropriate TRANSMISSION VERIFICATION TEST. Refer to 68RFE TRANSMISSION VERIFICATION TEST .
No
- Go To 5.
- Remove the Transmission Oil Pan and Valve Body and check the following in accordance with the Service Information:
- CLUTCH TEST FAILURE
Did the clutch test fail in reverse?
Yes
- Go To 6.
No
- Test complete.
- Perform the appropriate TRANSMISSION VERIFICATION TEST. Refer to 68RFE TRANSMISSION VERIFICATION TEST .
- CHECK FOR FAILED REVERSE GEARSET SPLINES
Working through the windows in the bottom of the case, check for a failed Reverse Sun or Annulus spline as follows:
- Hold the Transmission Output Shaft by holding the Transmission Manual Lever in the park position.
- Apply the 4C clutch using 30-40 psi shop air at the apply port in the center bulkhead.
- Attempt to rotate the input annulus gear and drive shell (the drum that encloses the two rearmost gearsets).
NOTE:Due to the overrunning clutch, the gear and drive shell normally rotates in one direction only.
Can the drive shell be rotated?
Yes
- Repair internal transmission as necessary in accordance with the Service Information. Check the reaction annulus gear weld to the reverse carrier, and the reaction sun gear weld to the 4C clutch hub.
- Perform the appropriate TRANSMISSION VERIFICATION TEST. Refer to 68RFE TRANSMISSION VERIFICATION TEST .
No
- Go To 7.
- CHECK THE DRIVE SHELL WELD
- Release the output shaft and the 4C clutch.
- Apply the L/R Clutch only using 30-40 psi of shop air.
- Attempt to rotate the drive shell as in the previous step.
Can the drive shell be rotated?
Yes
- Repair Transmission as necessary in accordance with the Service Information. Check the drive shell weld to input annulus gear.
- Perform the appropriate TRANSMISSION VERIFICATION TEST. Refer to 68RFE TRANSMISSION VERIFICATION TEST .
No
- Disassemble and inspect the input clutch assembly. Check the Reverse clutch reaction plate snap ring. Check the OD and Reverse clutch seals, discs, and bleed orifice (in the OD/Reverse clutch piston). Check the Reverse hub and shaft. If no problems are found, check the L/R clutch assembly and repair as necessary. If all clutches are OK, replace the Transmission Solenoid/TRS assembly in accordance with the Service Information.
- Perform the appropriate TRANSMISSION VERIFICATION TEST. Refer to 68RFE TRANSMISSION VERIFICATION TEST .
- CHECK FOR INTERMITTENT OPERATION
- Intermittent gear ratio DTCs can be set by problems in the Input and Output Speed Sensor circuits and/or Speed Sensor Ground circuit.
- Remove the Ignition Switch Feed fuse from the TIPM.CAUTION:
Removal of the Ignition Switch Feed fuse from the TIPM will prevent the vehicle from being started in gear.
WARNING:The Ignition Switch Feed fuse must be removed from the TIPM. Failure to do so can result in possible serious or fatal injury.
- Install the Transmission Simulator (special tool #8333A, Simulator, Transmission).
- Check the Speed Sensor wiring and connectors for good connection, then perform a wiggle test using the Transmission Simulator (special tool #8333A, Simulator, Transmission).
Were there any problems found?
Yes
- Repair as necessary.
- Perform the appropriate TRANSMISSION VERIFICATION TEST. Refer to 68RFE TRANSMISSION VERIFICATION TEST .
No
- Test complete.