GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

Knocking or clunking noise occurs when operating the vehicle in high gear or coasting in neutral at 16 km/h (10 mph).

A worn or damaged universal joint

Replace the worn or damaged universal joint. Refer to Universal Joint Replacement - External Snap Ring .

The side hub counterbore in the differential is worn oversize

Replace the differential case and/or side gears.