Initial Inspection and Diagnostic Overview

Transmission Cooling

Inspection and Verification

NOTICE: When a transmission has been disassembled to install new parts or a new or remanufactured transmission has been installed, the transmission fluid cooler and/or auxiliary transmission fluid cooler and the transmission fluid cooler tubes must be cleaned and backflushed to keep contaminants from entering the transmission, causing internal damage.

NOTE: Backflushing and cleaning the transmission fluid cooler tubes, along with following all the normal cleaning and inspection procedures during disassembly and assembly, will keep contaminants from entering the transmission, eliminating a repeat repair. For additional information, refer to Automatic Transmission/Transaxle &/or Transmission Control Systems for 5R55S or Automatic Transmission/Transaxle &/or Transmission Control Systems for 6R80, Transmission Fluid Cooler Backflushing and Cleaning.

When internal wear or damage has occurred in the transmission, metal particles, clutch plate material or band material may have been carried into the torque converter and transmission fluid cooler. These contaminants are a major cause of recurring transmission failure and must be removed from the transmission fluid cooling system before the transmission is put back into use. Install a new transmission fluid cooler and/or auxiliary transmission fluid cooler and backflush the transmission fluid cooler tubes.

When transmission fluid leakage is found in the transmission fluid cooler, install a new transmission fluid cooler.

If the fault is not visually evident, GO to Symptom Chart - Transmission Cooling or GO to Symptom Chart - NVH. Symptom Chart - Transmission Cooling Symptom Chart - NVH