I just put a poly trans mount in the Z28 and now I have this vibration at 55mph. The mount seems to be softening up and getting smoother but it still vibrates at 55.

I hear that the mount is taller, so you have to shim the cross member down a bit to correct drive shaft angle. How far do I go? A washer or two good enough?


thanks
-Ted

 

with a poly transmount your ganna feel a lil more vibration due to the poly mount. As long as it's not clunking like if it was broken or loose bolt. If your worried about it, check the bolt after a few miles and make sure it's tight to ft lbs specs. I never heard of a shim being used but if my memory serves me..you do use a washer on the outside bolt.

 

If it's the Energy Suspension (probably most common one) one just don't use the metal plates that come with the kit and shave the two pre-load bumps on the mount down and you'll be fine. No vibration from mine.

 

they do make a poly mount specific for our cars , not sure which one it is ,
the vibrations are not that bad, its a sports car arent vibrations and loud sounds a part of life