Silverado 1500 2WD V8-4.8L VIN V (2006)
Fluid Pump: All Technical Service Bulletins
A/T - 4L60-E, 4L65-E Fluid Leak From Bell Housing Area
Bulletin No.: 06-07-30-016
Date: July 18, 2006
TECHNICAL
Subject:
4L60-E, 4L65-E Automatic Transmission Fluid Leak from Oil Pump or Bell Housing Area (Remove Small Burrs On Torque Converter Hub, Pump
Drive Slots and Replace Torque Converter Hub-to-Oil Pump Seal Assembly (243))
Models:
2006 Buick Rainier
2006 Cadillac Escalade, Escalade ESV, Escalade EXT
2006 Chevrolet Colorado, Corvette, Express, Silverado, SSR, TrailBlazer
2006-2007 Chevrolet Avalanche, Suburban, Tahoe
2006 GMC Canyon, Envoy, Savana, Sierra
2006-2007 GMC Yukon
2007 GMC Yukon XL
2006 Pontiac GTO
2006 HUMMER H2, H3
2006 Saab 9-7X
with 4L60-E or 4L65-E Automatic Transmission (RPOs M30 or M32)
Condition
Some customers may comment on an automatic transmission fluid leak. Upon further investigation, the technician may find fluid leaking from the oil
pump or bell housing area. This leak may be very slight with only dampness of one or two drops of ATF observed at the bottom of the bellhousing.
Cause
Investigation of 2006 transmissions has shown small scratches or cuts in the torque converter hub-to-pump seal (243). These scratches or cuts may be
caused by small burrs on the torque converter hub, pump drive slots.
Correction
Verify that the leak is coming from the oil pump or bell housing area by the use of oil dye in the transmission. Refer to Fluid Leak Diagnosis in SI. Clean
the transmission suspected area of all residual oil and drive the vehicle to see if the dye begins to appear. If this is a vehicle with very low mileage and it
appears to have a small leak, it could have assembly oil in the bell housing which is not truly a leak.
