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View Full Version : Checked out my control arm bushings today...



Jon K
07-06-2005, 06:09 PM
is there supposed to be ANY play? The arm didn't shake freely at all, but when i pried on it with a screw driver, it moved pretty easily (not very easily) front to back. This is the LOWER control arm by the way, with the bigger bushing (750i bushing). It made a squeaky rubbery sound, I have a bad shimmy @ 55... ugh how do i determine if it is in fact this bushing.

Jeff N.
07-06-2005, 06:15 PM
I replaced mine a bit ago. No shimmy but I had beat the crap out of them at the track. My inspection showed:

- thrust bushings showed some small cracks/rubbing in around the plastic center
- you could displace the thrust arms somewhat with slight prying
- had a fair amount of tramlining
- no obvious tears or failures visible

When the new bushings were installed, no displacement at all. Very stiff (750). Tramlining gone.

I did both control arms and thrust arms; bushings only - not the whole arm. Ball joints were fine. About $100 for parts and pressing at the machine shop.

Jon K
07-06-2005, 06:18 PM
I replaced mine a bit ago. No shimmy but I had beat the crap out of them at the track. My inspection showed:

- thrust bushings showed some small cracks/rubbing in around the plastic center
- you could displace the thrust arms somewhat with slight prying
- had a fair amount of tramlining
- no obvious tears or failures visible

When the new bushings were installed, no displacement at all. Very stiff (750). Tramlining gone.

I did both control arms and thrust arms; bushings only - not the whole arm. Ball joints were fine. About $100 for parts and pressing at the machine shop.


Ok, so with a BRAND NEW, 100% good bushing I should not be able to move the control arm in any vector other than pivoting it? Is it at all possible to press the bushings out and press new ones in while arms are in the car? The arms have... 30k on them, lemforder. There are 750i bushings in there but I am either doing M5 bushings (solid rubber) or Grunt urethane bushings.

Jeff N.
07-06-2005, 06:29 PM
I could "roll" the thrust arm with my hand. That is, grab it and rotate it around it's axis. Couldn't do that with with new ones.

I pulled the steering knuckle off bottom of the strut and took it to the shop. I did not pop the ball joints; typically kills them.

Jon K
07-06-2005, 06:31 PM
I could "roll" the thrust arm with my hand. That is, grab it and rotate it around it's axis. Couldn't do that with with new ones.

I pulled the steering knuckle off bottom of the strut and took it to the shop. I did not pop the ball joints; typically kills them.


http://e34.digital7.com/BMW%20Work/DSCN0577.JPG


So you took out every arm from the car side, undid the strut, disconnected sway bar and pressed the bushings into the unit?

Jeff N.
07-06-2005, 06:36 PM
Yes. I guess I must have undone the tie rod end.

mattyb
07-06-2005, 07:17 PM
hey there gentlemen. jst a qick question while ur here. are there grease nipples anywhere under therefor any of the arm bushes etc.

Jon K
07-06-2005, 07:44 PM
hey there gentlemen. jst a qick question while ur here. are there grease nipples anywhere under therefor any of the arm bushes etc.

no