Brake Pedal / Steering Wheel Shudder

[blakbearddelite]

After deciding not to sell the G8 in the last week, I've decided to do some maintenance on it and fix a few annoying issues.

One of them I'm not quite sure how to address. When I have my foot on the brake and the wheel turned, I feel a vibration in what feels like both the brakes and steering wheel. It doesn't happen when I turn (without braking) and it doesn't happen when I brake (without turning the wheel).

When I'm doing searches on the webs, I can't find anything specific to that situation. All web searches point to a warped rotor, but I don't think that's the case. What gives?

Click to read more...

 

[Mook]

Rod bearing.

 

[blakbearddelite]

Did they start putting rod bearings in brakes in the last five minutes? This must be a new development. I didn't see a thread on that.

 

[CMNTMXR57]

Rotor run-out (more or less warped rotors).

It probably happens in a straight line too, just not as prevalent.

 

[blakbearddelite]

If it was run-out, shouldn't it happen in braking with the wheel straight as well? I put in new pads / rotors last year, and the car was barely driven with the exception of this summer while the Mustang was down. It only vibrates with harder braking going into a turn.

 

[RICH17]

Odd situation. I'd get down there and make sure everything is tight and also lubed.

 

[blakbearddelite]

Do the brake booster and power steering share the same hydraulic system?

 

[boostedguy05]

Rotor run-out (more or less warped rotors).

It probably happens in a straight line too, just not as prevalent.

this.

 

[blakbearddelite]

I'm trying to figure out how in the hell the rotors got warped in the last year when I barely drive the car. Maybe it was two years ago that I replaced the brakes. But either way, there can't have been more than 8k miles on the brakes.

 

[bikrboy128]

check the lower control arm bushings for any play/rips in the rubber. worn out bushings could cause the shake you're describing
also take a look for any rust on the rotors. is the vehicle kept outside?

 

[CMNTMXR57]

As I said, it's probably not as prevalent in a straight line but still there.

Could happen from one good, hard run down.

Could've been one hard emergency braking

Could be from sitting (rust forming on the surface), then not being worn off evenly upon subsequent usage.

Could just be a bad (I.E. cheap) rotor with insufficient/varying thickness.

 

[blakbearddelite]

I had the LCA's replaced last year (or the year before) by Pontiac under the recall. I really should keep a log of when stuff has been done to the car. I can never remember. And yes, the vehicle is almost always outside.

 

[boostedguy05]

Could have a semi stuck pin in the caliper and it warped the rotor slightly, and when turning it puts more stress on that side and then you notice the shudder. could be 100 different things in the front end driveline / suspension.

tell you what, i will do you a favor and buy it really cheap come tax return time.

 

[blakbearddelite]

I change my mind every day about keeping it. I've seen some really nice lower mileage Q50's in my price range. I just promised myself I'd never get into two car payments at the same time. It's been nice socking away money the last few months with the new job and dropping full time daycare.

 

[Bruce Jibboo]

Lol my impala has rotors that vibrate just like that, prolly gonna tear into it wed

 

[blakbearddelite]

I would hope that if someone from a dealership was checking it out on a trade, that maybe they wouldn't put the car through the paces.

 

[boostedguy05]

sometimes they barely look at them. i was told the brakes on the journey with sub 40k mikes, were SHOT.

i told them to go back and look again, because i changed them that morning. one of the rears had locked up on me so i changed out everything and gave it all a good clean / lube job.



also rotors warped on the malibu right around 32k miles

crazy ship happens around here.

 

[boostedguy05]

I change my mind every day about keeping it. I've seen some really nice lower mileage Q50's in my price range. I just promised myself I'd never get into two car payments at the same time. It's been nice socking away money the last few months with the new job and dropping full time daycare.

come feb/mar, i will shoot you a super low offensive offer.

 

[b4black]

I put new AC Delco rotors on my Regal a couple of years ago. The better type with the black coating on them. I was changing a wheel bearing last month and noticed the backsides of both fronts looked like shit. Big chunks of metal flaking off. They were delaminating. The front side that I could see through the rims were very good.

You might want to pull a wheel and take a good look. I've had something similar happen the rear rotors as well.

 

[blakbearddelite]

I did promise myself that I wouldn't be cheap next time and that I would buy the rotors with the coating on them to prevent rusting. I think it is only another few bucks per rotor.

 

[SMKE EM]

I'm trying to figure out how in the hell the rotors got warped in the last year when I barely drive the car. Maybe it was two years ago that I replaced the brakes. But either way, there can't have been more than 8k miles on the brakes.

Easily. Rapid heat dissipation warps even brand new rotors. Many people take their cars through car washes after long hot drives, or hit big puddles of water when it's raining.

Most people think "oh it's no big deal" but that actually destroys and cracks parts....

 

[CMNTMXR57]

I put new AC Delco rotors on my Regal a couple of years ago. The better type with the black coating on them. I was changing a wheel bearing last month and noticed the backsides of both fronts looked like shit. Big chunks of metal flaking off. They were delaminating. The front side that I could see through the rims were very good.

You might want to pull a wheel and take a good look. I've had something similar happen the rear rotors as well.

2 years around here, when subjected to water, snow, salt, heat and brake dust will cause even the best surfaces to still rust. All that painted "rotor hat" section on either side does is slow the process, but it'll still rust eventually.

 

[Intel]

could try rebedding the brakes pads. A lot of surface rust from sitting can mess with the transfer layer and a rebedding can help clean it up if the deposits aren't too thick/uneven.

 

[SMKE EM]

Take your rotors off and have them turned at oreillys. I think it's like $10/rotor. Chances are your rotors are warped a little by now anyway. See if it fixes the issue, slap some new pads on too since it's apart and rotors are turned

$50~ total see if it fixes the issue

 

[Bob Kazamakis]

Rotors don’t warp