I posted a few days ago re a cyclical vibration I've been experiencing and that I was (still am) leaning towards drive shaft couplers - thanks to C5Nuke for his insight on this job. I've since done a little more testing to try to isolate the vibration before diving into the coupler replacement.

I jacked-up the read of the car, took off traction control and then spun the rears wheels up (50 mph). No, no one or thing was in front of me! With the rear wheels on, there's a hell of a vibration. With the rear wheels off, there's zero vibration. For poops and grins, I did the same with my 2012 Charger, only with the wheels on - zero vibration.

I recognize the axles on the Vette (or the Charger) are not fully loaded, as they would be rolling down the road, but don't know enough to know if that would (or should) make a difference. If everything is in balance and aligned correctly, there shouldn't be any vibration, correct?

For those thinking the obvious (tires), all four rim/tire assemblies for the Vette have been road forced by a good shop in town so I know it's not them (I also know it's not the rim/tire assemblies because this is the second set of rims/tires I've had on the car and the vibration is the same regardless of the set-up).

Now I'm not sure what to think. Diff?

 

I would 1st try to narrow it down to which side is causing the vibration--After that look for
A mismatch to the wheel studs or something preventing the wheels from sitting flat and square on the rotor hub
Secondly I would suspect the CV joint on the vibrating side OR a loose/broken "toe" adjustment assembly or a loose/broken "camber" adjt. assembly
With the wheels on-- have someone start the car--hold the brake and step on the gas (power braking it) see it the wheel assemblies move ---they normally will have a little movement but if something is loose or broken they will "jump around a lot-
Finally make sure the brakes are all on tight and look OK---as well as the parking brake