Control arm and ball joint replacement

[Isambard]

Originally Posted by digitaljok

Just found out today from the alignment shop that I will need new tension strut (front control arm) bushings. Bushings have already been replaced once, current mileage is 88k. I am very interested in knowing why BMW specs only one bushing replacement. Was set on picking up Meyle HD bushings, but now am confused as to whether I really need completely new arms. For the record, the shop says that the ball joints are still OK. Even if they weren't, couldn't I just replace those as well and keep the original arm? Thanks in advance!

I'm interested to know how/why the bushes are the second lot in there at only 88k miles! I replaced mine at 99k miles and they were the original ones.

As for your dilemma I think you have to weigh up the costs, along with engineering practices. How much is a new front thrust arm over there? How much would it cost for you to replace the bushes on your originals, remembering engineering practice dictates (as well as the ethos of 'while you're there'..) that you replace the balljoints also, as these have been in there the same length of time as the bushes.

Then you have BMW saying that you can only replace the bushes once. The only reasons I can think of as to why they state this is 1. They obviously want you to buy another one. 2. Having pushed through the bush and then put in another one, the diameter of the casting may increase enough to be outside of their press-fit tolerances, and so be far enough out of their safety factor. 3. The life-cycle of the part itself. Meaning that, these bushes/balljoints have a life-cycle of say 90k miles, then having a second bush/balljoint in there means the life-cycle of the arm itself may be less than 180k miles-due to internal stresses/strains over time etc.

If, however 2 and 3 are just a load of old bollocks, then it must be 1!!

If it was something else other than the PITA job mine turned out to be I'd totally agree with amacman in that I'd change the bushes (I'd also change the balljoints too though) and keep an eye on things. However that would also depend on whether you want to keep an eye on things from there on in. Me personally, speaking from experience (post #15) I would change the arms and be done with it.

So, in essence, like amacman said, its up to you on what you want to do-cost/time/effort....

[Sundayjumper]

Originally Posted by Isambard

2. Having pushed through the bush and then put in another one, the diameter of the casting may increase enough to be outside of their press-fit tolerances...

Is it possible there's some confusion here between X5 & E39 arms ? The layout is the same but the E39 arms are aluminium and I can imagine they're less tolerant to repeated changes than the steel arms on the X5.

FWIW, I'd have no qualms about changing the bushes again on an X5. The only thing to weigh up is the time saving of buying new arms with the bush already pressed in. If you're DIYing that could save you a lot of grief.

[imalabil]

What are the torque specs?
Bill

[ronh95]

Getting ready to tackle this tomorrow morning. Since I don't have access to a large press, it was almost as cheap to get new Lemforder tension struts w/bushings installed, than just bushings and have them pressed locally. They wanted $75/bushing to press them at Napa Auto Parts here in So California! I asked him 'are you sure?' he was adamant. I'm guessing they don't do a lot of this work at those prices and probably would have jacked up the job anyway! = )