Thrust Arm Bushing-Can you visibly see cracks/wear? - The Unofficial BMW M5 Messageboard (m5board.com)

tripleD · 8th May 2007, 04:49

I'm getting some unusual cupping in the front left out edge tire. I'm not getting any clunking or trammeling. I also just had a PSS9 installed a few months ago (cupping occured b/f install). Was wondering if it were possible to detect wear/cracking from a visual inspection of bushing or do you have to just take a chance when replacing the bushing/arm hoping this solves the problem?

E55AMG2 · 8th May 2007, 05:02

I think it'd have to be disassembled to tell. I just replaced mine with monoballs....so we'll see how good they are

ard · 8th May 2007, 06:00

Quote:

Originally Posted by E55AMG2

I think it'd have to be disassembled to tell. I just replaced mine with monoballs....so we'll see how good they are

+1

It is really hard to visually inspect- mine looked fine but were beat once I could look at them closely.

A

palantirion · 8th May 2007, 08:30

If it's on a lift it's pretty easy to inspect the thrust arm bushings with a good flashlight. Depending on how the wheel is turned you can see both sides of each bushing.

BeastJaTT · 8th May 2007, 09:36

I read people changing the oem bushing with X5 bushings...does anybody know where to buy them off the net? or there are any other bushing better than the X5 ones.

E55AMG2 · 8th May 2007, 19:00

Quote:

Originally Posted by BeastJaTT

I read people changing the oem bushing with X5 bushings...does anybody know where to buy them off the net? or there are any other bushing better than the X5 ones.

Its pretty much; OEM, OEM X5, Powerflex, or Dinan Monoball

Nabio · 8th May 2007, 19:04

Try braking fairly lightly around 50ish mph, slowly slowing yourself down. Then brake a little heavier on the next pass. If you can feel any wobbling in the wheel I believe that's a good warning the bushings aren't doing so well.

As for the X5 bushings, I believe the keyhole goes in opposite than the standard OEM 5 series bushing, but I may be wrong because I know very little about suspensions.

palantirion · 8th May 2007, 19:33

Here is a thread on swapping out M5 bushings for X5. Read the WHOLE thread.
Installing X5 bushings, also: Crevier sucks!

Lscman · 9th May 2007, 15:55

The other option is Vines arms off ebay. Some folks are getting significant miles on them with positive results. They have a heavy duty 4 wheel drive X5-style aftermarket bushing already pressed into complete arms with ball joints for about $130/pr.

Performing Imports · 9th May 2007, 16:25

Quote:

Originally Posted by tripleD

I'm getting some unusual cupping in the front left out edge tire. I'm not getting any clunking or trammeling. I also just had a PSS9 installed a few months ago (cupping occured b/f install). Was wondering if it were possible to detect wear/cracking from a visual inspection of bushing or do you have to just take a chance when replacing the bushing/arm hoping this solves the problem?

Cupping is caused by the toe setting. Too much negative toe will cause out side cupping, too much positive toe will cause inside cupping. The thrust arm bushing will not cause tire cupping. A failed/failing thrust arm bushing will only cause vibrations. For it to have an impact on tire wear, the bushing would have to be so bad that you would get a clunking sound when braking. More than likely you have too much negative toe in. Most alignment shops put negative toe in BMW's because setting the toe at factory spec - which is zero toe - makes the car a little twitchy, meaning the steernig is very sensitive to input and on cupped road roads you have to constantly correct. We put negative toe in as well, but only 0.2 degrees which takes time to get right and costs more than $49.95

which is what most alignment shops charge for an alignment. I think some of the shops put in so much toe because they know they will sell twice as many tires on that car and then to cover it up blame the car, suspension, bushings, road condition and outer stellar planetary alignment as the cause for the cupping. Find a very good alignment shop and pay them to do it right.