Steering Wheel Shakes When Braking

[kalans]

Hello everyone, my name is Kalan and I am having an issue with my wifes 2008 Pontiac G5 which is just about 99k miles. I have been researching and working on the G5 several times in order to fix this issue, and have not found the cure yet.

Vehicle
2008 Pontiac G5 sports edition 2.2L drum brakes in rear 99k miles

Problem
Steering wheel rattles/shakes when braking, which happens at various speeds. The G5 hasn't had any service recently when the issue has shown up.

What I Have Done
I have replaced both rotors, both sets of brake pads (ceramic), tightened all bolts to manufacturer's recommended specs, lubed caliper guide pins, bled the brake lines in front, pulled the ABS fuse (issue still present) and replaced it back, had a mechanic look at it which the only code he found was for the RR ABS sensor not being in sync along with the TPMS (tire pressure system) code as well (which the light for it has come on and off when driving at high speeds, but eventually goes away).

The issue has is still present from before and after all that has been done including replacing the rotors. I have come to many dead ends on researching, and even came to suspecting the steering column to be an issue although I do not hear any clunking or have steering issues. While replacing the brake pads I noticed the inside pads being more worn which had 1/3 life remaining while the outside pads had 2/3 left (still went ahead and replaced them). When compressing the calipers the dust boots did have an air bubble, which I tried to tuck in but was not successful which I discovered that led to them wearing a hole in them (since two weeks ago). I have ordered two brake caliper repair kits, which I will perform tomorrow.

Recalls Fixed
Power Steering, Ignition.

Any help would be great, thanks!

 

[YelloEye]

Well.... I'm stumped. Here's to hoping the caliper replacement helped...

 

[John Matrix]

I've dealt with some strange re occurring brake pulsations on my 1995 Camaro even with brand new brake rotors. To narrow it down I'd pull your rotors off and inspect them to confirm it is the brake system and not the steering.

If there is hot spots or other uneven wear indicators on the rotor that is where the pulsations are coming from. I've had to have brand new rotors turned at a shop 2 weeks later because of hot spots that developed. Rotors very rarely will actually warp, pulsations usually come from uneven pad deposits fused to the rotor surface, and it makes them feel warped when you hit the brakes.

Aftermarket rotors can be cheap, the lighter (less material) they have, the worse they are at absorbing heat. If your hard on your brakes when you are braking in new pads, uneven deposits can develop which will make them feel warped.

I hope your calipers fix the brakes. There is also a hub flange (where the rotor meets the hub), should be free of rust so the rotor is mounted straight. You might also want to check for rotor runout, you need a dial indicator to do this.