Inspection and Verification
When fluid leakage is found in the fluid cooler, install a new fluid cooler.
When there is evidence of transmission assembly or fluid contamination due to the following transmission failure modes, install a new fluid cooler.
- major metallic failure
- multiple clutches or clutch plate failure
- sufficient component wear which results in metallic contamination
Symptom Chart
| Condition | Possible Sources | Action |
|---|---|---|
| Transmission overheating | Damaged OTA fluid cooler. | INSTALL a new OTA cooler. |
| System leaks. | INSPECT for leaks. REPAIR as necessary. | |
| Incorrect fluid level. | ADJUST to correct level. | |
| Fluid condition. | INSPECT according to instructions under Fluid Level Condition Check. REFER to AUTOMATIC TRANSMISSION - 5R55N . | |
| Damaged, blocked, reversed, leaking, or restricted cooler tubes. | INSPECT cooler tubes. REPAIR as necessary. | |
| Incorrect idle or performance. | REFER to SELF-DIAGNOSTICS - EEC-V - GASOLINE & NGV . |
SYMPTOM
Transmission Fluid Cooler Flow Test
Special Tool(s)
Scheme 59
Note. The engine idle, transmission linkage/cable adjustment, fluid level and line pressure must be within specification before carrying out this test. Refer to AUTOMATIC TRANSAXLE/TRANSMISSION EXTERNAL CONTROLS for adjustments. For additional information on engine idle diagnosis, refer to SELF-DIAGNOSTICS - EEC-V - GASOLINE & NGV . For additional information on fluid level check, refer to AUTOMATIC TRANSMISSION - 5R55N . For additional information on line pressure, refer to AUTOMATIC TRANSMISSION - 5R55N .
Scheme 60
Scheme 61
Scheme 62
Scheme 63
- Place the transmission range selector lever into PARK.
- Raise the vehicle on a hoist and place suitable safety stands under the vehicle. For additional information, refer to «JACKING & HOISTING»(ref-232595-S06496072622006051700000) .
- Hold the large drain plug with a wrench, and remove the small (center) fluid level indicating plug using a 3/16 inch Allen key.
- Install the special tool into the pan.
- Remove the cooler return line (upper line) from the fitting on the transmission case.
- Connect one end of a clear hose to the cooler return line and route the other end of the hose to the special tool in the pan.
- Remove the safety stands and lower the vehicle.
- Start the engine and run it at idle.
- With the engine running, raise the vehicle on a hoist and place suitable safety stands under the vehicle. For additional information, refer to «JACKING & HOISTING»(ref-232595-S06496072622006051700000) .
- Once a steady flow of fluid (without air bubbles) is observed, remove the hose from the special tool and place the hose in a measuring container for 15 seconds. After 15 seconds, place the hose back onto the special tool. Lower the vehicle and turn the engine off. Measure the amount of fluid in the container. If adequate flow was observed, approximately 237 ml (8 oz) will be in the measuring container. The test is complete. Reconnect the cooler line, and install the fluid fill plug.
- If the flow is not liberal, disconnect the hose from the cooler return line and connect the hose to the cooler inlet (lower fitting) on the transmission case. Reconnect the cooler return line to the case (upper fitting).
- Repeat Steps 8-10. If flow is now approximately 237 ml (8 oz) in 15 seconds, the cooler lines and auxiliary cooler must be cleaned. Refer to «TRANSMISSION FLUID COOLER - BACKFLUSHING AND CLEANING»(ref-204562-S04420678422005111300000) . Carry out this entire test after carrying out the backflushing and cleaning procedure. If, after carrying out the backflushing and cleaning procedure, the flow is still not adequate the installation of new cooler lines and/or auxiliary cooler must be carried out. If the flow from the case is still not adequate after the installation of new cooler lines and/or auxiliary cooler (237 ml [8 oz] in 15 seconds), the pump and/or torque converter may be at fault. Carry out the appropriate procedures for diagnosis and repair.