Removing the Thrust Arm Ball Joint

[Adnan]

Hi,

I'm getting mentally prepared to replace the thrust arms on my E34 535 (parts on their way from, whom else, bma). Two questions come to mind:

First, is the BMW ball joint puller available for rent from any of the major parts places? Has anyone had success using a generic puller?

Secondly, Bentley does not offer a torque spec for the nut on the ball joint for the thrust arm (perhaps I missed it?) but does mention 68 lbs-ft for the ball joint on the control arm. What should one torque to, 68?

Thanks for your input,
Adnan

[Jeff N.]

Hi Adnan,

When I did mine, I pulled the entire "yoke" if you will that connects to the bottom of the strut housing. Unbolt the thrust arm, unbolt the control arm and then used a Craftsman 3 arm gear pulled to pop the ball joint from the tie rod.

Took the whole arm to the local midas and had them press in the new bushings.

I think if you go this route you can use a gear puller (carefully) to pull the tie rod ball joint. It's the most accessable by far and I got it clean and didn't tear the boot. The thrust arm and control arm ends are more hidden and I recall that you would need a special puller to pop them loose.

This was the approach suggested by Bill R. and it worked great.

Cheers!

Jeff

PS - can't remember what the torque is. Can look it up if no one else posts it...

[Jeff N.]

Thrust Arm bushings (http://www.bimmer.info/forum/showthread.php?postid=5945#poststop)

[Bill R.]

I was going to make a strut arm change page but very few people expressed any interest when i asked about it so it got shelved. At any rate you can remove the bottom bolts that attach to the strut as seen here and then remove the sway bar link on one end. Then remove the tie rod from the steering knuckle with a conventional puller Then remove the bolts that attach the thrust arm to the frame and the lower control arm to the frame. Then you remove the whole thing as a unit as pictured. I was going to show you how to separate the thrust arm ball joint in a vise with a hammer but I thought that a number of you might not have a vice of sufficient size to support it... so I thought about it and decided to come up with an easy field fabricated method that anybody could separate the joints with. By supporting the knuckle on a couple of impact sockets (Improvise here) I supported it solidly so it couldn't deflect or more and then I hit the ball stud one whack, didn't even take a very hard whack and they pop right out when supported as shown..
http://www.bimmernut.com/%7Ebillr/images/Thrustarms/strutboltscopy.jpg

http://www.bimmernut.com/%7Ebillr/images/Thrustarms/lowercontrolarmunbolted%20copy.jpg

http://www.bimmernut.com/%7Ebillr/images/Thrustarms/Thrustarmonsockets1%20copy.jpg

http://www.bimmernut.com/%7Ebillr/images/Thrustarms/socketstaremoval%20copy.jpg
[

[Bill R.]

and yes the torque is 68.5






I was going to make a strut arm change page but very few people expressed any interest when i asked about it so it got shelved. At any rate you can remove the bottom bolts that attach to the strut as seen here and then remove the sway bar link on one end. Then remove the tie rod from the steering knuckle with a conventional puller Then remove the bolts that attach the thrust arm to the frame and the lower control arm to the frame. Then you remove the whole thing as a unit as pictured. I was going to show you how to separate the thrust arm ball joint in a vise with a hammer but I thought that a number of you might not have a vice of sufficient size to support it... so I thought about it and decided to come up with an easy field fabricated method that anybody could separate the joints with. By supporting the knuckle on a couple of impact sockets (Improvise here) I supported it solidly so it couldn't deflect or more and then I hit the ball stud one whack, didn't even take a very hard whack and they pop right out when supported as shown..
http://www.bimmernut.com/%7Ebillr/images/Thrustarms/strutboltscopy.jpg

http://www.bimmernut.com/%7Ebillr/images/Thrustarms/lowercontrolarmunbolted%20copy.jpg

http://www.bimmernut.com/%7Ebillr/images/Thrustarms/Thrustarmonsockets1%20copy.jpg

http://www.bimmernut.com/%7Ebillr/images/Thrustarms/socketstaremoval%20copy.jpg
[

[Mr. BILL]

That's pretty slick Bill R. I have a question though. If I just replace the bushings, couldn't I just take that assembly to a shop and have them pressed out, without removing the ball joints?

[Adnan]

Hi,

Thanks for your, as usual, excellent suggestions. Perhaps I should also replace the control arm bushings while the whole thing is out?

What is the failure mode and symptom of bad bushings in the control arms? Should they be replaced anyway at this point (125k miles)?

Thanks,
Adnan

[Bill R.]

mileage, if you check them after removing the assy. you'll find that both ball joints will have play in them. So for this reason if i were doing my own i would just go ahead and replace both the thrust arm and the control arm if I planned on keeping the car for quite a while yet....Patrick can give you a pretty good price on the thrust arm with the bushings installed, the ones in these pics had 90k something miles on it and the boots were torn and the joints were loose , so at you're mileage i would probably just replace the assy. unless the ball joints felt nice and tight which is unlikely.








Hi,

Thanks for your, as usual, excellent suggestions. Perhaps I should also replace the control arm bushings while the whole thing is out?

What is the failure mode and symptom of bad bushings in the control arms? Should they be replaced anyway at this point (125k miles)?

Thanks,
Adnan

[Jeff N.]

My ball joints were OK. I did both the thrust arm and control arm bushings.

[Hector]

making a page on strut arm change. I seriously think you should do this given the crisp images you have just shown. You almost don't need any words to describe the procedure. I'm certain many will benefit from this.
"If you build it, they will come," or If you make it, they will see...

[Adnan]

.