Don't know for sure...I always figured it was the fact that when you were stopping, the car was driving the engine...force pushing one way...then when you let off the brake, the engine was pushing the car...force the other way. Maybe I'm whacked, but my truck had the same symptom and the mounts fixed it. I'm not going to complain about it.

Took about 8 trips to the dealer to get it fixed.

I agree with CHessMaster completely and have fixedmany GM trucks with the special lube that were doing the exact same thing. I no longer have access to the lube and would appreciate the GM part number. Thanks, Tigafila

_________________
'05 CRD Limited: 174k mi Euro Torque Converter, EHM, ORM, Racor fuel filter, Original Rocker Arms, Amsoil everywhere
'98 Dodge Ram 2500 Cummins 24 valve extended cab short bed
'01 Jinma 4wd diesel tractor

Im sure someone said it already but its bad u joints on the drive shaft. I got mine replaced and it fixed it.

_________________
2005 CRD Sport
Mods: Glasspack, OME HD Struts & Springs, 2" Daystar lift,
255/70/16 General Grabber AT2's on MOAB's
ORM&EHM with great success!
TJM T17 Bumper, 50W KC HID's