Instructions for Checking and Replacing front Control Arms and Bushings on a BMW E46

Pictures in this instruction are from a 2003 330I with ZHP Performance Package and may not look like others in the E46 family but should use the same procedure. This procedure references the passenger’s side of the car and has a headlight leveling bracket; the driver’s side does not.

Raise the vehicle with and appropriate jack and place a Jack Stand under the frame rail for safety. The image below shows the control arm and the control arm bushing. The Ball Joints are the two forward mounting points and the control arm bushing is the piece on the rear side attached with 2 hex head bolts.



Checking the Ball Joint
Once the car is suspended from the frame with no support under the Control Arm grasp the rotor at the 2 O-Clock and 7 O-clock positions and turn it back and forward. There should be no movement in a good ball joint. The Video below shows the movement of a bad ball joint. Note; from a jack point of view, a second person watching for movement may be helpful.

http://youtu.be/kuOvH4Z6mDY

Removing the Lower Control Arm and Control Arm Bushing
Remove the (7) Philips screws (not shown) that attach the cover between the front bumper and the front cross member under the car. It’s not necessary to remove it completely and I just let it hang.

Loosen the 13mm nut in the center of the control arm (also pictured). Loosen the nut until you can no longer see the bolt threads. Now use a hammer on that same nut in an upward motion to dislodge the bracket from the control arm. This is a very tight fit and mine did not move until significant blows of the hammer finally mover it. Once dislodged remove the nut and tuck the bracket up and out of the way.

Remove the two attachment bolts from the Control Arm Bushing and leave it lay.

Remove the Ball Joint nut that attaches to the spindle (wheel side pictured below) using an 18mm box wrench (using a socket seems to have a clearance issue with the ABS sensor). I also included a picture of what I needed to do because of a stubborn bolt. The Allen Wrench show was to stop rotation of the ball stud.





This step to remove the nut from the Ball Joint that attaches to the frame is the most difficult step of the procedure. This is a 21mm nut and a 3/8 Drive Socket is not readily available. There’s not enough room to fit that big of a tool into this space either. Solution; a 13/16 inch socket is a near exact conversion to 21mm so, that and a short flex head ratchet should do the job. Note: this is torqued tight and takes some mussel to get broken loose. You will also only get one or two clicks of the ratchet so plan to be there for a while. Note: the picture below was taken with a camera from a spot your head will not fit into, prepare to work in the blind.



To remove the control arm from the car you need to dislodge the ball joints. This can be done using a Pickle Fork and a hand sludge hammer (pictured below). You need to set the Pickle Fork wedging it between the ball Joint and the spindle (pictured below). Give it a few taps to engage it. Once in place give the Pickle Fork end several hard blows until separation occurs. A length of 2 x 4 lumber can be handy for keeping the strut assembly out of the way after the Ball Joint is free. Repeat procedure on the engine cross mount Ball Joint. It should take lees force to remove.





Reassembly

To make life simple the Control Arm Bushing should be attached to the control arm prior to installation. This bushing is a very tight and its sticky rubber so, lubrication helps. Sounds good but, its rubber and it reacts to petroleum so, DO NOT USE OIL, GREASE OR ANY PETROLEUM PRODUCT, unless you want to do this again when the bushings swell. The alternative method is soap and what was suggested to me by a BMW Tech was window cleaner. Sprayed it on the control arm then both sides of the bushing and smacked it into place with a rubber mallet.

Reassemble the Control Arm Assembly into the car buy slipping the bushing end into the pocket then the center Ball Joint in to its respective hole. Hand thread the nut onto the Ball Joint to keep it in place. Next reattach the Control Arm Bushing and tighten both screws till it’s seated. There should be no gap below and the recesses on the face (counter bores) should be fully engaged with the protrusions around the I.D. thread (Bosses). Reattach the Headlight Leveling Bracket and the outer Ball Joint. The last thing to do is tightening everything up. There are Torque specks for this but good luck getting a torque wrench in to do that. Use your best judgment on tightening.

Hope this helps and Happy Motoring,

-3ZHPGUY-