No it is not the tires or rims, replaced both axles and hubs, changed top motor supports and lower motor motor, replaced tranny mount, even changed spark plugs, wires and coil packs. The car starts to vibrate at
35 mph especially going up a hill, then mellows out after around 45 but you can still feel the vibration but not as bad as at 35 mph. I have had it at a GM dealer and they are scatching their head. The car has 110,000 miles, now they are telling me it might be the planetary gear in the tranny, the tranny was rebuilt at 77,000. Has anyone out there had any problem with their Grand Prix?- posted
17 years ago