Analysis of Leakage

Power Transfer Unit (PTU)

Analysis of Leakage

NOTE: There are 2 different PTU (Power Transfer Unit) configurations used depending on the transaxle. The repairs made for leakage on these 2 different PTU (Power Transfer Unit) s may vary depending upon the type and location of the leakage. The specified tools called out will allow seal replacement without causing damage to the PTU (Power Transfer Unit) case and drive gear.

NOTE: Inspection of the seal's mating journal should be performed every time a seal is replaced. The mating part/journal should be replaced if it has any of the following conditions: Radial wear groove that can be felt by running a finger nail across it where seal lip runs. Scratches, pitting, galling, nicks or other shaft damage under or near where the seal lip runs. Discoloration or coked oil on the shaft where the seal lip runs. Shaft corrosion under or near where the seal lip runs. Sharp edges or burrs on the shaft lead in chamfer. NEVER use emery cloth on journal finishes, replace the part.

The PTU (Power Transfer Unit) may leak different color fluids, red ATF (Automatic Transmission Fluid) or tan/brown/black gear lube. The PTU (Power Transfer Unit) and transaxle seals prevent these types of fluids from leaking. It is important to note which color of fluid is leaking to determine the most appropriate service procedure. The residue of red ATF (Automatic Transmission Fluid) should be cleaned from the PTU (Power Transfer Unit) to prevent a inaccurate diagnosis of a red ATF (Automatic Transmission Fluid) leak following the repair.

PTU (Power Transfer Unit) Leaks From the RH Side

Vehicles Equipped with Aisin AW21 Transaxle

NOTE: The intermediate shaft seal functions as a dust seal and is not a source of a red ATF (Automatic Transmission Fluid) leak.

If the leak is red ATF (Automatic Transmission Fluid) , this indicates the transaxle seal is leaking and needs to be replaced. For additional information, refer to Transfer Case.

If the leak is tan/brown/black gear lube, the PTU (Power Transfer Unit) cover seal is leaking and needs to be replaced. This cover seal is located on the PTU (Power Transfer Unit) cover, behind the deflector. For additional information, refer to Cover Seal procedure.

Vehicles Equipped with 6F35 Transaxle

If the leak is red ATF (Automatic Transmission Fluid) , this indicates the intermediate shaft seal is leaking and needs to be replaced. For additional information, refer to Intermediate Shaft Seal - 6F35 procedure.

If the leak is tan/brown/black gear lube, the PTU (Power Transfer Unit) cover seal is leaking and needs to be replaced. The cover seal is located on the PTU (Power Transfer Unit) cover, behind the deflector. For additional information, refer to Cover Seal procedure.

PTU (Power Transfer Unit) Leaks From the LH Side

Vehicles Equipped with Aisin AW21 Transaxle

NOTE: The compression seal functions as a dust seal and is not the main source of the red ATF (Automatic Transmission Fluid) leak.

If the leak is red ATF (Automatic Transmission Fluid) , this indicates the transaxle seal is leaking and needs to be replaced. For additional information, refer to Automatic Transmission/Transaxle &/or Transmission Control Systems.

If the leak is tan/brown/black gear lube and not at the vent, check the non-serviceable PTU (Power Transfer Unit) inboard seal for leakage. If the PTU (Power Transfer Unit) inboard seal is leaking, the PTU (Power Transfer Unit) must be replaced. If the leak is from the vent, the PTU (Power Transfer Unit) may be overfilled. Determine if the red ATF (Automatic Transmission Fluid) has entered the PTU (Power Transfer Unit). If red ATF (Automatic Transmission Fluid) has entered the PTU (Power Transfer Unit) , the transaxle seal and PTU (Power Transfer Unit) must be replaced. For additional information, refer to Automatic Transmission/Transaxle &/or Transmission Control Systems and Power Transfer Unit (PTU) .

Vehicles Equipped with 6F35 Transaxle

If the leak is red ATF (Automatic Transmission Fluid) , this indicates the transaxle seal is leaking and needs to be replaced. For additional information, refer to Automatic Transmission/Transaxle &/or Transmission Control Systems.

If the leak is tan/brown/black gear lube, the PTU (Power Transfer Unit) may be overfilled and leaking from the vent. If the PTU (Power Transfer Unit) is overfilled, adjust the level as necessary. If the leak is not at the vent, the non-serviceable PTU (Power Transfer Unit) inboard seal is leaking and the PTU (Power Transfer Unit) must be replaced. For additional information, refer to Power Transfer Unit (PTU) .