GM Service Manual Online
For 1990-2009 cars only

Checks

Cause

Noise is related to vehicle speed. Whine may diminish or go away after an upshift to Second Gear

Input Internal Gear (637)

Gears are worn or pitted

Input Carrier Assembly (640)

The thrust washer mating surfaces are rough or pitted

Input Sun Gear (642)

Gears are worn or pitted