My dealer claimed I had a damaged right front control arm (called a wishbone in the www.realoem.com listing) on my 2002 MCS. I couldn't see any sign of damage and when I asked them to show me he said a lot of damage is not visual and will only show up when you try to do an alignment! So how did he see it to tell me it needed replacement?

Anyway, the strut mount is damaged and I am going to replace that. I am trying to decide whether to go ahead and replace the control arm at the same time to play it safe. Has anyone had to replace the front control arm? According to my Bently manual a couple of BMW special tools are required to pop the arm off of the inner and outer ball joints. Are there any suitable substitutions (like a regular ball joint remover) that would be available at a tool store? I am having a hard time telling how these tools work based on the pictures in the manual. Any ideas?

I am going to do one more inspection tonight to see if I can determine if there is any damage or not. Then, with your input, I'll have to decide if I am going to tackle this or not.

Thanks

 

Have you driven the car over potholes?

 

C4- Good question. The answer is no, however, I got the car used with about 12,000 miles on it. So I can't say that it hasn't hit any pot holes, just that it hasn't happened while I owned it. I don't know how long the strut mount has been cracked. The dealer pointed it out after getting my "inspection I" done this year (same time he claimed I needed a new control arm).

 

I just had to change the left front control arm (cm)on my 02 MC. I'll bet the MCS is the same. You do not need specialized tools to do this. However, ordinary mechaninc tools are necessary. There is only one ball joint per side and it is attached to the cm at the bottom of the spindle (drive axel outer bearing carrier). I removed the two bolts holding the ball joint on to the spindle and after removing the other bolts holding the cm in place and the connection to the sway bar, the cm should be free. The ball joint can then be removed from the cm by backing the nut on the taper off enough to clear the threads. Support the cm and placie a block of brass or copper (not steel) against the nut and striking it sharply with a hammer to break loose the taper. The other corner of the cm has a rubber isolator which needs to be removed. I used a standard gear puller to get this off. These are available at a tool rental place or your local auto machine shop should beable to help or if you are are like me and insist on being a "dofer" (do for yourself), buy a puller. Assembly is the reverse. Be sure to clean to all surfaces with emphasis on bolts, threads and nuts, then tighten or torque as required.

When you have the old and new cms sid by side, compare to see and or verify damage. It should be obvious. If no differences are apparent, get a second opinion.

Good luck.

 

deerharb

Thanks for the info. It never occured to me to unbolt the ball joint from the spindle first so I could work on it from my bench. I was under the impression that the bolt coming through the cm at the bend (connecting to the sway bar maybe?) was also a ball joint taper fit into the cm. So you didn't need to press that one out? I am glad, this is sounding easier than I thought.

Was the rubber isolator bad or did you feel that it should be replaced while you have the cm out? One write up of a similar operation for a 3 series BMW stated that inserting that isolator was the hardest part, he ended up having a shop with a hydraulic press put it in. I have no problem getting a puller. By the way, the official "bushing tool" for removing and inserting that isolator lists for $311.00.

Thanks again for the tips. I just wish I could tell ahead of time whether I really needed the cm or not.

 

I actually went out and looked at my cm and you are right. The bolt at the bend is another ball joint. My face is red. This second ball joint is mounted to what I call a floater plate that bolts to the engine cradle, so if you remove those bolts too you will have the cm in hand with two ball joints to remove. Use the same technique for both. That is, loosening the nut and striking the loosend nut using a brass or copper drift to prevent thread damage.
The sway bar attachment is not a part of the process.

My car has 12,000 miles on it so the isolator was in good shape. If the rubber is badly cracked or loose then replacement is warranted.

There are various pullers available. Along with the puller, you will need something similar to what is used to remove bearings from a shaft, to grip and get behind the isolator. This item is a split plate with a hole in the center for the shaft. The plate is held together with an upper and lower bolt. The bolts allow some adjustment of the plate around various sizes of shafts.

Sorry for the somewhat vague descriptions of the tools needed. The main thing to keep in mind is that you have to adapt and inovate to use these standard but non specialized tools to avoid the $311 specialized ones. The combined cost of the puller and the bearing plate has got to be about 1/4 of the BMW thing.

If any of this explanation does not make sense, come back to me.
Hang in there.

 

IJ,
Check various threads around here. I had my strut mounts replaced under warranty. It's a known issue w/ the MC and MCS. The dealer replaced w/ a heavier unit. Might have contributed to the arm damage. Also check threads for arm damage, couple have pics detailing the weak spots. There seems to be a lot of cracking also, more so than you should see in a new car but just my .02. Could always use that as an excuse for adjustable mounts and new tubular control arms.

 

I agree the strut mount is a known issue. But when I tried to get the dealer to do it he claimed that it must have been from hitting something, although even he admitted there was no mushrooming on the sheet metal the mount bolts to. He said, as evidence, that the front lower control arm and outside ball joint are damaged. When I asked him to show me the damage, the story changed to "well a lot of damage is not visible and you won't know until you try to get an alignment". So how did he know it was damaged to begin with? Anyway I have decided to change out the strut mount myself, then if I still can't find any damage to the control arm I am going to have it aligned, if that falls in place I am going to leave it. If not then I'll change out the control arm and ball joint myself.

Maybe I am a poor thread searcher, I could only find threads on failed rear control arms. Same with tubular replacement, rear only. I'd love to do some upgrades and this is a good excuse but its not in the cards for me right now.