Hey all! Hoping someone with more BMW knowledge can help me to diagnose an issue.
2009 528xi, 75k
The car has a shudder on high speed or heavy braking. It comes through the steering wheel.
Swapping 4 zimmerman rotors and pads did not correct it.
Swapping wheels and tires also did not assist.
A local BMW indy looked at it and aligned it (and recommended I try wheels/tires as they were shot anyway) and said the bushings all looked to be good.
I am thinking is has to be control arm or suspension related, but I don't know if there are any tricks to further diagnose- or do I need to just start tearing it apart.
Any thoughts (or smart comments) are appreciated!
First of all, don't just tear apart suspension parts randomly. Since your car is newer, you shouldn't have any dramatic or unusual parts failing that are causing the problem (but not always). By swapping rotors and pads, do you mean replacing them with new ones? The same with the tires. Are the tires balanced? If you can't figure it out, have a shop fix it because they have the training to only replace what's at fault.
Yes to all- new Zimmerman rotors- new pads, a set of rotary forged beyern wheels and some P zeros.
I have brought it to the local dealership and a local independent bmw mechanic- they were not particularly helpful.
A worn outer tie rod end would be my first guess as I've seen an unusually large number of those on E60's.
Worn thrust arm bushings are another possibility but they typically amplify existing problems like rotor runout or wheel imbalance rather than being a primary issue. I think that may have been a run on sentence.
A leaking or blown front strut is my third wildass guess. Do check back in when you resolve this, I have the curiosity.
Thank you! I will keep you updated.
Check out the ball joints and the front and rear brake lines.
The mechanics should have been able to fix it. Your car is only 5 years old!
In addition to other suggestions, like control arm bushings ball joints and tie rods, a wheel bearing that is just starting to develop play will make you think there is something wrong with the brakes.