This is really pissing me off!

[ED1RTY 2]

Alrighty, since our cruise on saturday my car has been vibrating like a bitch when i get to over 100 kmph. It does it slightly up to 100 kmph. I have checked all my tyres, flipped my rear ones (I have to for the camber wear) all four wheels have since been balanced but i havnt had a wheel alignment done just yet.

I have just installed new lower control arm bushes and have just ordered new adjustable swaybars links and nolathane mounting bushes. My swaybar looks to be pushing forward more than it normally would (pushing through the standard rubber so its almost metal on metal.) I was suspecting this to be my problem.

I have checked my rear shock mounts etc and have seen no wear there. I had my whole suspension system checked out by autoalign but they (nor me) can figure out what the hell this vibration is. Could it be my swaybar? Should i just get a wheel alignment? (even though in theory they can only align the front?) Could it be my halfshafts are bent?

I have no idea atm what it could be so if anyone could shed some light on this subject it would be highly appreciated. I have alot of long distance driving to do over summer so id like to get it all fixed!!

Cheers

Chris

Edited November 22, 2006 by sakdbma

[bravo 35]

Wheel alingment won't usually cause vibration - more likely to be a worn part somewhere - wheel bearing, balljoint, bush, rack end, etc, or a warped wheel (which you would have picked up when the wheels were balanced so not that).

[kiwipetrolhead 1]

Wheel alingment won't usually cause vibration - more likely to be a worn part somewhere - wheel bearing, balljoint, bush, rack end, etc, or a warped wheel (which you would have picked up when the wheels were balanced so not that).

"Wheel alingment won't "- I agree with that.

In all my years I have never seen a worn wheel bearing cause a vibration. Yes, many people have thought a bearing might be the cause, but I have never found a true case for it. And I have replaced worn wheel bearing numerous times, but there was no vibration prior.

I have never come across a worn ball joint causing a vibrating either, although I accept there might be a case for that one.

A warped, or buckled wheel can certainly cause a vibration. Even mags can become buckled. One of my 540's 'new' mags has one slight buckle on the inside edge in fact, so I'll get it fixed this week or next. I have no idea how it got the buckled, but there you go. In my case, the buckle does not cause any vibration though - well, not up to 160kph at least.

The most common cause of a vibration is a worn out Uni Joint on the drive shaft, but this is not a common problem on BMWs because they have a different type of joint. Sometimes an Auto Trans fault can cause a vibration, but the most common cause I know in BMW is a warped rear brake drum - yes, the brake drum for the handbrake, not the brake disc itself. In fact, my 540 has a slightly warped left rear brake drum and the car has a vibration because of that (the vibration was there before the mag got buckled). I am in no hurry to replace it though, it's no big issue at present. But if the vibration is more noticeable, it should be sorted out for sure. So my suggestion is to check your brake drums first.

The other cause can be worn suspension bushes, as suggested above. This occurs quite a lot in e21's front suspension, but it's not a real common problem on most cars. However, I understand 5 series can have a bit of a problem in the rear as well, so perhaps 3s do as well.

Paul

[hotwire 352]

Maybe worth checking driveshaft centre hanger/support, or maybe rubber doughnut at the front?

[ED1RTY 2]

Checked, found to be rear shock tower support + f**ked steering rack. Getting it all sorted when the car is out of the panelbeaters, maybe try and get it replaced as part of the inurance deal lol