Hello gang, Just a note of encouragement for others considering the replacement of the upper ball joint/guide joint on a W107/114/115. This is a relatively easy job, maybe 2 hours per side with diddling around, 30 minutes of actual labour. Note that, while it is theoretically possible to replace JUST the ball joint and not the entire a-arm, the price difference is only about $60, and for that you get new upper mount bushings and you avoid the labour of trying to drill out the riveted-in ball joint plate etc. Not worth it, IMHO.
Here are a couple of possibly-helpful tips: 1. To aid the removal of the joint from the knuckle, I used the force of the spring itself in addition to a ball joint separator. I did this by inserting a used brake pad between the bottom of the upper arm and the subframe at the hinge point. This effectively means that the upper arm (instead of the shock absorber) serves as the limit stop for the spring. This puts the upper ball joint under tension, aiding the ball joint separator in its work. 2. To aid in reassembly, I used a short piece of 2x4 and a trolley jack to freeze the upper ball joint from turning during the tightening. Helpful tools: Trolley jack 19mm combo-wrench x 2 19mm socket Extension pipe that fits over the wrench Ball joint separator (gap width 3/4" width, gap depth 7/8", gap throw 2") Piece of 2x4 wood, about 8.5" long Here are the steps for we mortals without special tools and a lift/pit: NOTE: AT ALL TIMES LEAVE THE SHOCK ABSORBER CONNECTED, OTHERWISE YOU COULD BE INJURED. REMOVAL a) With the front wheel on the ground, jack up the car from the opposite corner (ie. if you are doing the driver's side, jack up the rear passenger side) until you can slip a sturdy object such as a brake pad between the upper arm and the subframe. If you ARE using a brake pad, put the lining facing DOWN on the subframe, since the arm itself is more of a point contact and may crumble the lining. Don't use anything too thick; you don't want to create too much tension. b) Lower the rear of the car onto the ground, loosen and chock wheels etc appropriately, turn steering wheel all the way towards the side you are working on, remove key, lock steering wheel, then raise and FIRMLY SUPPORT the front on the side where you are working, remove wheel etc. Check that the brake pad is still firmly planted and is indeed serving as a limit stop. c) Loosen but do not completely remove the locknut on the guide joint. You want to get it loose enough so that you can get it off once the ball joint separates, but not so loose that there's ANY risk of it being stripped/sheared off when the joint lets go. d) Apply the ball-joint separator and tighten until CRACK! the joint separates. This will be loud and shocking. e) Loosen the locknuts/bolts securing the arm to the subframe. Remove the locknuts, but LEAVE THE BOLTS in place. f) For safety (in case your shock absorber has failed and cannot serve as a limit stop), securely position a trolley jack under the bottom arm and compress the assembly slightly (1/2-inch or so, plus any movement caused by mushy subframe mounts). This will also serve to take some tension off the upper arm/brake pad deal. g) Carefully loosen the locknut to free the upper ball joint from the steering knuckle. MAKE SURE THAT YOU DO NOT ALLOW THE STEERING KNUCKLE TO FALL TO ONE SIDE, THUS POSSIBLY DAMAGING THE LOWER BALL JOINT. You can now remove the brake pad if you hadn't already. h) Carefully lower the bottom arm until the shock absorber stops the arm. It should not travel very far before stopping. i) You can now use the trolley jack to support the knuckle (at the wheel hub) while you remove and replace the upper arm. INSTALLATION j) With the new arm fully secured to the subframe, insert the ball joint stub into the knuckle and tighten the locknut. It will tighten to a point and then the balljoint itself will begin to rotate. Do not fret. k) Position a piece of 2x4 vertically between the leading edge of the upper arm and the wheel well stiffening ribs beside the shock absorber. With the trolley jack, carefully raise the lower suspension arm in order to place the 2x4 under reasonable pressure. The upper ball joint will be under compression via the knuckle from below and the 2x4 from above, thus freezing the upper ball joint so that you can tighten the locknut. Voila! D. _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com