Just bought an '03 z06. It has a cyclical vibration starting at 50 mph and on up. I bought new Goodyear super car tires all around. I had the tires balanced twice at the Goodyear dealer and once at a hot stuff tire place for an additional $40.00. It drives just fine and has no vibration in the wheel. All of the vibration is felt in your feet on the floor or in your seat. I had the rear axle serviced. Any help. It drives me crazy.

 

Clutch slippage? or possibly an exhaust leak or exhaust system rattle? I believe the 03 Z06 uses the transaxle (axle/transmission combined), so the drive shaft is mounted front of the transaxle...(correct me if I'm wrong). I need to get under one of the newer models[:@]

 

did it do this after the tire change,any warrante,does it get worse as you go faster

 

Since ya don't feel it in the wheel, my first suspect is the"u" joints.