From bmw-digest.v4.n412 Wed Apr 10 10:01:01 1996
From: "Rick Kjeldsen" <fcmk_at_watson.ibm.com>
Date: Wed, 10 Apr 1996 12:26:33 -0400
Subject: Re: E30 M3 Control Arm Replacem

I havn't seen anyone give a decent reply, so let me. I've done this job about half a dozen times.

>1. Removing and replacing the bushings that attach the trailing ends of the
>arms to the chassis. Is there a cheaper way to handle this than with the $125
>puller/installer sold through BAS (no, I don't have access to a hydraulic
>press)?

The easiest way is pull off the arms and take them to a shop. They will probalby charge you $5-10, but the job is so easy for them, it should not be much more. Most good garages and many machine shops will have a press.
Otherwise you can rig up a special tool to press the arm out of the bushing, and then pound out the old bushing. The first time I rigged up a tool by bending a 2" long piece of threaded rod into a U, putting it through the hole in the arm and mounting a gear puller on the end. Then I used the gear puller to press out the arm. Definitly a Pain in the Butt. I modified the tool to press the arm back into the bushing, but there it worked even worse. Find a press!
Once the arms are out you can pound the bushings out of the bracket, and gently pound the new one in. To pound them out I used a large socket designed for the front axle nuts of a full sized Blazer (you need something to pound on when they start to get inside the bracket). It worked. When you pound them back in, put a flat plate on top and pound on that to avoid deforming the metal jacket. Overall, doable, but not recomended.
Find a Press :-)

>2. Any recommendations on inserting the new arms into the bushings? The
>bushings have about 1/4 inch holes but the tips of the arms are about a 1/2
>inch in diameter

You have to lube the holes. BMW sells a special lube that evaporates in half an hour. That way you can theoretically install the arms, put the car on the ground where the arms will rotate within the bushing till the lube evaporates, leaving them in the proper position. I've had trouble getting the lube from a dealer (they don't sell it in small containers) and I've never been able to get the job done before the lube drys. Lately I've been using silicone as a lube. It works well to get the arm on, and seems to disappear within some days or weeks to leave the arm and the bushing solidly attached (yes, you can drive the car in the mean time ;-)

> (I assume you install the bushings into the chassis first,
>than shove the tips of the control arms in). It looks like an impossibly
>tight fit.

Nope. You want to install the bushing in the bracket, and onto the arm then bolt the bracket onto the car. Don't worry, it will fit.

>3. I know on E28's you need to pre-load the car than tighten down the
>through-bolts on the bushings. How do you pre-load the M3? I assume there is
>a mark that shows the proper orientation of the bushing into the chassis, but
>then you would have to make sure you have the control arm inserted the right
>way relative to the bushing, right? And if that's so, you'd have a hell of a
>time getting

There is a mark to show the orientation of the bushing to the bracket, but none to show the orientation of the arm to the bushing. When I press the arm into the bushing I usually orient it with respect to the bracket the same way the old one was, so it doesn't have to rotate very far, then let the lube do the rest.

rick
'87 325es on it's third set of control arm bushings. '90 325iX on it's second
'88 M3 on it's first