I just got new tires and brake rotors on my Monte two weeks ago. I have since developed a shake at 55-65mph, its pretty bad. I have had it back in the shop 3 times this week and they can't figure it out. My mechanic has rebalanced the wheels, checked front suspension and is at a loss.

Any suggestions from anyone on what it could be?

 

Your inner cv joints could be the problem but they usually start at lower speeds and continue to shake through the range, but.... if you let off the gas it usually evens out, check and see if this is the case.

If it is you can replace the cv joints but realistically it's easier to just replace the axle as by the time you remove the axle, remove the boot, buy a new boot, remove cv joints, install new cv joints, grease and re assemble a new axle is just quicker and easier lol

 

I agree with ohara. You might here a clicking noise when you turn the wheel even at lower speeds if it's the CV.

 

Could be an alignment issue or a bad tierod or 2.

 

I would rotate the tires and at least take them out of the equation. Were your new tires a decent brand? Some low cost tires can be a performance issue. Put someone elses tires and wheels on your car for a test run and see it the problem goes away.

Do you smell brake pads while driving? Could be the new calipers are faulty and hanging up, not releasing and heating up your rotors real crazy like...

 

Check your axle nut, and make sure there are the correct weights on the wheels (but if this shop is even remotely competent they should have that done right). Could be an axle issue, or a loose caliper bolt. Touch each of your front wheels after driving it, they should be the same temperature. If one is different, there's some sort of issue there.

 

Thanks for all your suggestions guys!
The shake doesn't go away when I let off the gas But I think I found the problem, or at least a problem.
After I made the post yesterday when I got home the passenger front was definitely hotter than the rest. I jacked up the front end and I can't spin that wheel at all by hand. With both wheels off the ground and in drive that wheel still won't spin! The brake caliper is stuck tight.

This definitely has to be fixed. But I wouldn't have thought it would create a shake that acted like a bad tire so close. Evidently when they pried open the caliper to put the new rotors on the caliper must have gotten damaged. The caliper maybe has been sticking ever since. I have replaced brakes on all of my other vehicles over the years with no issue. Is there a "special" method for opening the caliper on later models without damaging them? I did hear of one of my buddies calipers being damaged on his truck when a mechanic replaced the pads.

 

A C-clamp has worked fine for me in most scenarios. I don't think W-bodies have the weird twisting pistons on the calipers... Maybe bleed that caliper? Otherwise you may need a new one..

 

I got it jacked up in my shop now, getting ready to replace the caliper myself. I hope this fixes the shaking too. Do you think this could have been the source of the shaking?

 

Definitely. Vibration from pulsing of the ABS.