Initial Inspection

Inspection and Verification

CAUTION: When internal wear/damage occurs in the transmission, metal particles, clutch plate material and band material can travel into the torque converter, the fluid cooler tubes, the in-tank transmission fluid cooler and the auxiliary transmission fluid cooler, if so equipped. These contaminants are a major cause of recurring transmission concerns. To prevent future concerns, remove these contaminants from the cooling system before placing the transmission back into use. Refer to Automatic Transmission - 4R70W/4R75W or Automatic Transaxle/Transmission - Torqshift for fluid cooler flow testing, backflushing and cleaning, torque converter cleaning and inspection, and flushing. 4R70W/4R75W - Automatic Transmission Torqshift - Automatic Transmission

1. Visually inspect for obvious signs of mechanical damage, incorrect component installation and system leaks. Repair as necessary.
^ Install a new or remanufactured radiator when fluid is found leaking from the in-tank transmission fluid cooler. For additional information, refer to Cooling System.
^ Install a new O-ring when transmission fluid is found leaking between the radiator transmission oil cooler and the transmission oil cooler fitting (not the cooler line into the fitting). For additional information, refer to Component Test. Component Tests
^ Install a new auxiliary transmission fluid cooler if there is leakage from the fluid cooler. For additional information, refer to Auxiliary Transmission Fluid Cooler. Transmission Cooling
2. If the fault is not visually evident, GO to Symptom Chart. Diagnosis By Symptom