Thread: E39 Faq....
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Unread 08-20-2007, 10:35 PM   #52

Name: Dan
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Your Ride: 540
Originally Posted by Hotswimmer
Now, the hard part – pressing the ball joint stud out of the steering knuckle. It is in there TIGHT. I would not do this job without a ball joint press of the type you see in image #9 and #10. I have read posts from guys who say they've been able to remove the ball joint using a pickle fork, or by banging on the top of the stud. You're on your own if you decide to go that route. I rejected that option from the start. Space is just too limited, and you're talking about banging around on aluminum suspension components here. I bought the ball joint tool at - (do a search on "ball joint") - it cost me about $40, but there are other sources and price ranges.

HOWEVER YOU DO IT, DON'T DON'T DON'T DAMAGE THE BALL JOINT AND BALL JOINT STUD IF YOU'RE JUST GOING TO CHANGE OUT THE BUSHINGS AND WILL BE RE-USING THE OLD THRUST ARM AND BALL JOINT. If you're replacing the whole thrust arm, then this isn't an issue. The steering knuckle will look like image #11 when you finally get the ball joint stud out.

5) Now we're ready to remove the bushing side of the thrust arm from the frame. This is easy by comparison to the last step. Image #12 shows you what it looks like in place.

Image #13 shows the 21mm socket wrench on the bolt that goes through the center of the bushing and holds the thrust arm to the frame. You can also see the end of the bolt in Image #5. You may need to jiggle the steering back and forth a little bit to get the socket wrench on the bolt – I did this just by grabbing the brake rotor and turning the steering a tad. There's not a lot of extra room to maneuver. You'll also need to have a 21mm combination wrench on the nut to keep it from slipping.

Once you have the nut off, pull the bolt out and you can drop the thrust arm. Again, you may need to jiggle the steering a bit this way or that to give yourself room to pull the bolt. Image #14 shows how the frame side looks with the thrust arm removed. Image #15 shows the old thrust arm with bushing, ball joint and retaining bolt and nut. At this point, you're halfway there on the driver's side, and the hardest part of the job is behind you.

If you're only replacing the thrust arm bushing and are re-using the old thrust arm and ball joint, this is where you will press the bad bushing out of the thrust arm and re-install the new one. I went with all new thrust arms, so I regret that I can't provide you with any counsel on this step. I understand it is possible to do this yourself, though it's a lot less trouble to simply take your old thrust arms to a mechanic's shop that has a hydraulic press and remove/replace your bushings that way.

6) Image #16 is a picture of the new Lemforder thrust arm. Leave the protective cap in place over the ball joint stud until the last minute when you are ready to push it into its hole on the steering knuckle. Wiggle the bushing side of the thrust arm into its place in the bracket on the frame of the car. Push the 21mm bolt back in and thread the nut back on. DO NOT TORQUE THE BOLT DOWN AT THIS TIME! Just put the nut on the bolt and hand-tighten it. Image #17 shows the new thrust arm in place on the bushing/frame side.

7) Remove the protective safety cap and insert the ball joint stud in its hole on the steering knuckle. Thread the 22mm nut onto the stud and tighten it. As you tighten the nut, it pulls the ball joint into its proper position – there's nothing special you have to do here. See Image #18. Using your torque wrench, tighten the 22mm nut to 80Nm (59 ft-lb).

8) Reposition (raise) the steering knuckle on the strut and tighten the pinch bolt. Using your torque wrench, tighten the pinch bolt to 81Nm (60 ft-lb). Again, this took a 16mm wrench on the bolt and an 18mm wrench on the nut on my car.


10) Use denatured alcohol or lacquer thinner to clean your brake rotors if you grabbed them with your hands at some point during the procedure. Put the wheels back on the car and torque down the lug bolts. The lug bolts are 17mm, and should be torqued to 120NM (89 ft-lb) plus or minus 10Nm (7 ft-lb).

10) NOW we're going to tighten the bushing bolts on the thrust arms. The car needs to be LEVEL and SITTING ON ITS TIRES up on blocks or ramps, about 8 inches off the ground in front AND back. The car needs to be at spec ride height before you torque down the bolts. In addition to a full tank of gas (remember this?), you need about 150 pounds in each front seat, 150 pounds in the middle of the back seat, and 45 pounds in the trunk. If you're really anal you can measure and adjust the ride height further following the procedure in the Bentley manual, but this gets you plenty close enough. NOW you can get under the car and torque down the bolts that hold the bushing side of the thrust arm to the frame. Torque these 21mm bolts to 110Nm (81 ft-lb).

11) Re-install the sway bar brackets, making sure that the little nub on the rubber bushing fits in the corresponding hole in each bracket (See Image #5). Torque the 13mm nuts to 24Nm (18 ft-lb).

12) Lower the car to the ground and enjoy your shimmy-free ride! Incidentally, it is not necessary to have an alignment done following this procedure.
thanks to Randy for this writeup and pictures.
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