Brake Questions and Wheel Shake

[Emeraldage]

I have an 89 na don't know if brakes were any different in different trims and years.

Anyways I got some seriously steering wheel shaking 60mph+. Tires/Wheels balanced. The shaking occurs from front right wheel as I can see the hood bouncing on the right side... I've had the wheel moved to the rear. Both rear wheels are a slight bit bent and the front are fine. I notice when I stop the steering wheel moves slowly as well, and the car moves back and forth as well as the wheel pulling to the right a bit when I brake. So I believe I have a badly "Warped Rotor". Anyone concur?

Also more about the brakes. I just randomly tested to see how good they are by slamming hard on the brake at 70. Went about a half second without even slowing down. THen my face came off as it slowed down to 40 and then it stopped slowing down as quickly. Also making a "Vrrrrr" sort of sound, kind of a deep vibration sound, (Assuming warped rotor sound). It's fine for everyday driving but once I get the 7mgte in and all I want to make sure it's set well for good stopping power. Also it's not just low pads we had checked the car about two months ago and the pads were around 70%.

Low on money as I can't swap yet but brakes come first for safety. Any idea on what's going on here? Need to replace fluids? New rotors and all? I'd pay a bit for drilled or slotted rotors for the nice look and longer life and not looking dirty nor rusting.

 

[Emeraldage]

Also I just remembered.. When I put the non factory wheels on it I think that's when the vibrations started. Maybe the tire is somehow damaged and not perfectly rounded and the tire shop moved the wheels but not the tires? (They're directional tires they had to dismount and all).

 

[KicknAsphlt]

Are you running wheel spacers at all? I had a similar problem right after I bought my car -- would shimmy while cruising about 60ish. One day my buddy asked me if I had a bent rim, so I pulled the wheel and noticed a few things; previous owner put 1/4" spacers on and didn't put longer studs in, so the lugs were only engaging for the first 1/4" of thread...ended up stripping the lug nuts a bit and the wheel was loose enough to wobble...but thankfully not completely come off. I pulled the spacers, put new lug nuts on, and the shimmy was gone. Just a though.

Another possible thing could be the wheel was improperly balanced. For a time, I had my wheels balanced with a 'static balance' (no lip weights anywhere on the rim), where they only use the stick-on weights on the inner surface of the rim hoop (about centerline of the width). Had an annoying vibration constantly. Went back to having them put lip weights on the inner lip and using the stick-on weights up near the face of the wheel instead of centerline, and things have been gravy ever since.

**Edit** Also, about the brakes -- I've never known brakes to be so badly warped that it causes a shimmy while driving. If you don't feel an increase in the shimmy/shuddering when you hit the brake pedal, it's probably not your brakes. I suppose it's also possible that you have a bad hub bearing causing this.

 

[tyang82]

Sounds like bad tires. If your steering wheel shakes when you hit the brakes, its your rotors. If you're driving 60 mph and it shakes, its your tires.

 

[Emeraldage]

Thanks guys. I don't remember there ever being spacers on the wheels. And when I had them balanced and all they never said anything.

 

[Maple191]

I had both front wheel bearings completely worn out, and it would constanly viabrate at high speeds. They had no play in them but I found only when I took off my rotors and spun the hubs could I feel the bearings being pooched.