PontiacBonnevilleClub.com

This weekend I replaced the rear brake rotors and pads on my '01 SSEi and what a cluster**** of an experience with stuck bolts! The worst was the driver's side which took a and a 2' breaker bar to get the caliper bracket bolts loose. While working on these I even saw the control arm moving. Passenger side was a little easier. Have people never heard of anti-seize compound?

Anyway I noticed today that once I got over about 70 MPH there was a vibration. My first guess is that the rear is out of alignment now, esp. after what I saw with the driver's side control arm while I was working back there.

I also dropped the transaxle pan and changed the fluid and filter--another PITA! The fold filter' nipple was nearly fused inside the trans. Seems to be my luck to run into little things that become big problems. I haven't done the rear brakes on this car before nor anything with the transmission. With the exception of a few breaks I was working on this stuff from about 10:30 in the morning to 7:30 in the evening. And I've done brakes and trans services before!

Any other thoughts about the vibration over 70 besides the alignment? Thanks in advance.

Did you rotate the tires at the same time? Could be you moved an out of balance tire to the front and now you notice it more. Or you could have a piece of trash pinched behind the wheel keeping it from being in perfect alignment?

No rotation done. Strangely it wasn't as bad on the way home tonight. Also checked the transmission fluid when I got home and it still needs more, maybe 1.5 quarts. I wonder if low ATF level could cause the symptoms? Going to get more ATF tomorrow and see what happens.

I'm debating on getting new tires right now so I figured the car will either go to the shop for a rotation and alignment OR take care of the alignment once some new tires are on.

Road force balancing could help with the vibration issue.

nos4blood70 wrote:Road force balancing could help with the vibration issue.

Could being the key word. These are have a shake at 70 and is hard to diagnosis. I would recommend putting a drain plug in the trans pan so you can easily refresh the fluid since you don't need to change the filter every time you do the fluid.

A deformed/defective rotor can/will absolutely make trouble and cause the wheel to not turn "true", causing vibration. It can also cause shuddering when braking and a pulsation feel in the brake pedal. Just because something is purchased new, that doesn't automatically mean that it's any good, especially nowadays when fewer and fewer parts are made in the USA . Cleaning the "spots" of crud and rust off of the axle surface before installing the rotor is a good idea too.

I hope it's not a defective rotor. I wire brushed everything before putting the new parts on. I ordered the stuff from Rock Auto and the rotors were Raybestos but, unfortunately, when I got them I saw the dreaded (to me) "Made in China" on the box. I try to avoid Chinese anything except food. There's no pulsation through the pedal and the vibration it had before the brake job is gone. ATF level is up to spec now and the vibes are still there but not nearly as bad as Monday.