cyclic vibration

[frltsta11]

I have a 97 coupe that has a vibration starting at 55mph. I replaced the tires and the vibration is still there. The tires have been balanced and the car aligned. What can be other problems that could cause this type of vibration?

 

[c4c5specialist]

Hi there,
Does the vibration happen when you are accelerating, or coasting to a stop?????
Do you have to be on the brakes or off????
Does it make a difference what gear you are in??????
Please let us know, and we can proceed.
YoursinCorvette, c4c5

 

[frltsta11]

the vibration doesn't start till i hit 55mph. This during acceleration.It smooths out a little at about 70mph. I have an automatic.

 

[c4c5specialist]

HI there,
If you put the car in neutral, at the speed indicated, is the vibration still there????
Is the vibration there in 3 as well as 4, at the speed indicated???
c4c5