GM Service Manual Online
For 1990-2009 cars only

Fluid Leakage Front Pump or Torque Converter Area - keywords clutch fluid no seal shift slip

Subject:Fluid Leakage Front Pump or Torque Converter Area

Models:2005 Chevrolet Avalanche, Express, Silverado, and Suburban
2005 GMC Savana, Sierra and Yukon XL
with 4L80E (RPO - MT1) or 4L85E (RPO - MN8)



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Fluid leak from the bell housing area of the transmission. Leak may appear to be from the pump, case or torque converter area. Transmissions in question were built in the July - August 2004 time frame (2005 model year).

Recommendation/Instructions:

Torque converters built in this time frame may have been mis-machined where the torque converter seal rides on the hub of the converter. This will be seen and felt (by using a fingernail) on the torque converter hub. Replacing the torque converter and hub seal will repair the leak.

Depending on the amount of fluid loss, there could be damaged clutches internal to the transmission. If excessive fluid loss is evident, inspect the forward and direct clutches for damage and replace as necessary.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.