Steering wheel shimmy on highway NOT caused by bad balance?
 

What, BESIDES bad balance on a tire, could cause a front wheel shimmy in the steering wheel at highway speeds???

Here is the story:

My 95 LS was smooth as silk in terms of wheel balance. This past Monday, I had a major tune-up done, which included "tighten suspension" and "inspect brakes". Upon leaving the repair shop, my steering wheel now shakes pretty badly at 70MPH and up. At some points, the entire car shudders.

What could be causing this?

Some items of note:

Wheels were properly balanced and car was smooth BEFORE the work was done. Then I left shop and got the shakes. Then I went back to my tire shop (not the shop performing the tune-up) and had front RE-balanced...to see ifthat was the problem...on a Hunter Road Force Variance balancer...the best there is. Therefore, I must rule out a bad balance.

Front rotors are pretty badly warped. Could this be a factor?

Axles were re-built recently. But havent had a problem with them...

Again..this all came about AFTER my car was serviced. SOMETHING was tightened or adjusted or moved by the mechanics. Of course, I went back to the shop and they claim they "cant feel a thing"...F-ing liars. So Im pretty much stuck to figure this out myself.

ANY ideas????

I hope you went to a shop that you trust.

Usually, when suspension is adjusted and the car is on a lift, you should only tighten all related bolts to that suspension down and then lower the car to the ground. Then, torque everything down with the normal weight being put on the suspension. Otherwise, you alter the suspension geometery of your car.

Or, your alignment is now off because they want you to come back and pay them more money.

Or, your rotors are so bad that even without braking, they are vibrating the brake/wheel assembly and it's being felt through the steering wheel.

Or, they forgot to torque the wheels down to spec.

Or, someone else may have different ideas. :)

the warped rotors can definitely cause that problem. since you know your rotors are warped, why not change them anyways? it might be the problem anyways, so why not do that. even though they aren't the problem, might as well do them, it isn't too expensive for brembo blanks, you never know, you can kill two birds with one stone.

why not just refute the charges until the shop fixes the problem Its pretty easy to tell if the car is shaking or not

did they rotate the tires. i just rotated my tires and i got the same exact thing that you have. i have yet to rotate them back because i am lazy but i am goin to re-rotate them. my problem is same down to every letter. weird shit. check balance too

Take someone from the shop for a ride on the highway, when it shakes ask them, "Can you feel that motherfvcker?" If they lie and say no, backhand them with a tire iron or wrench, open the passenger side door and push their ass out at 70 mph. Shakes like you describe are common on superbeetles. My struts were worn on the bug, when I replaced them, along with most of the front suspension, the shakes were gone. It may also be that the shop took it for a test drive and clipped something, that would knock your alignment off and possiboe cause symtoms like you describe.

First off does it shake all the time on the highway or only under braking?
If it does it under braking it probably is the rotor problem. If it does it all the time it could be a loose wheel or a seperated tire. How new are your tires? If you have a seperated tire on the back you might not feel anything but if you move it to the front you will notice it for sure. I had that done WOW.