My 86' Monte Carlo SS has been showing a strange problem. Everytime I reach speeds of 55mph+ the whole vehicle starts vibrating. The vibrations get worse as speed increases but stops DURING acceleration. When I left off from accelerating the vibrations come on again until my speeds drop below 55mph again. I just got new tires, and had them balanced. The problem is still here though. Any ideas what could be causing this? Thanks

Forrest

 

Are you sure they balanced them correctly or as closely as they could? Other than that, I'm not sure what it could be....Check to see if your tires are cupped at all or if there are any wires showing.

 

Have your tires rebalanced.

 

and check the drive shaft it could be off ballance or even bent

 

You might want to check the U-JOINTS.

 

bad U joints would show with acceleration, and at low speeds as well...would be more rpm related than speed. I would definately suspect the tires or rims, if that doesn't help check the alignment.