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Chazmati
01-27-2008, 04:47 PM
I need some help/advice. I'm replacing the thrust arms (aka upper control arms) on my '95 540i. I have new arms with bushings pressed in, new washers and self-locking 22mm nuts for the bushing end.

Problem: How in the #$%* do you get a wrench on that nut on the bushing end? It's really tight between the frame and the sway bar link bracket. This wasn't covered in the manual. Has anyone done this? The bolt end seems fairly accessible, but I'm assuming I'll have to hold the nut end with something to torque it down. Especially unclear is how I'll do this with the wheels on and car lowered.

Car is up on jack stands now, any help would be appreciated.

winfred
01-27-2008, 05:55 PM
the box end of most wrenches fit in there i find, if not you can unbolt the rear cross member partially and get the room you need, as for pretensioning the arm with the suspension unloaded i tighten the through bolt with the ball joint end sitting on the steering arm instead of down in it's hole, that's about the right position

calibra
01-27-2008, 06:00 PM
it is a job but its ok once you get going 22mm spanner on the tight part and then a breaker bar on the other and pull like mad once you get it going its ok and will come off with out to much fuss unless like me you have the bolt the wrong way then your have to drop a lot down just to get it out.
to torque it up your need the ramps or try jacking the car up then sliding blocks under the wheels so its up in the air but still on the wheels its what i was going to do until a friend said he had ramps

good luck

doogie
01-27-2008, 06:01 PM
The procedure I used, think I got it from either Bruno's site or Johan's, is to get a 22mm open end wrench, preferably an old one, and grind the sides down so that it slips in easier, otherwise the rounded part of it stops it going in properly.

calibra
01-27-2008, 06:03 PM
The procedure I used, think I got it from either Bruno's site or Johan's, is to get a 22mm open end wrench, preferably an old one, and grind the sides down so that it slips in easier, otherwise the rounded part of it stops it going in properly.


humm i must have a messed up setup i just popped a ring spanner on there turned the other end and the spanner locks in

doogie
01-27-2008, 06:08 PM
this (http://bmwe32.masscom.net/sean750/uca_bushing/Upper%20control%20arm%20bushing.htm) is what I was talking about; it's maybe only a problem on the E32, not the E34.

Chazmati
01-27-2008, 07:04 PM
Thanks Doogie! The "unreachable nut" is exactly what I was talking about. Aborted mission for today, will grind down an open end wrench and try again. Or maybe like Calibra mentioned I can try to get a box end wrench in the right spot and turn the bolt until it lines up and locks in.

winfred
01-27-2008, 07:15 PM
yea e32s are tighter then e34s at the nut


this (http://bmwe32.masscom.net/sean750/uca_bushing/Upper%20control%20arm%20bushing.htm) is what I was talking about; it's maybe only a problem on the E32, not the E34.

calibra
01-27-2008, 08:01 PM
just use a breaker bar i used two spanners joined up on the first side and when the nut cracked i smashed my leg on the disc, after what came out my mouth next door closed their windows lol

the higher you can get the car the better i think.
there is a very easy way i had to do it on the other side because some of the other parts i had to drop wouldnt move use one of these http://www.diy.com/diy/jsp/bq/nav/nav.jsp?action=detail&fh_secondid=9372884&fh_view_size=6&fh_start_index=6&fh_eds=%3f&fh_sort_order=-1&fh_sort_by=_price_rrp_min&fh_location=%2f%2fcatalog01%2fen_GB%2fcategories%3 c%7b10082%7d%2fcategories%3c%7b10084%7d%2fcategori es%3c%7b9181024%7d&fh_refview=lister&ts=1201482078193&isSearch=false
and cut the bugger off

calibra
01-27-2008, 08:08 PM
this (http://bmwe32.masscom.net/sean750/uca_bushing/Upper%20control%20arm%20bushing.htm) is what I was talking about; it's maybe only a problem on the E32, not the E34.

good link doogie i have saved it but you see in the picture where the unreachable nut is on mine they were round the other way so to get the arm out i had to drop all sorts down just to get the bolt out.
one side of the car is still round the wrong way but the other is right after cutting the bolt

winfred
01-27-2008, 09:59 PM
some goober must of had the front end apart and didn't use brain power to put it back together if those bolts were in backwards, they put it completely together on the ground and then attached it to the car

Ross
01-28-2008, 09:57 AM
the box end of most wrenches fit in there i find, if not you can unbolt the rear cross member partially and get the room you need, as for pretensioning the arm with the suspension unloaded i tighten the through bolt with the ball joint end sitting on the steering arm instead of down in it's hole, that's about the right position
Why didn't I ever think of that?

calibra
01-28-2008, 11:41 AM
some goober must of had the front end apart and didn't use brain power to put it back together if those bolts were in backwards, they put it completely together on the ground and then attached it to the car

Yep what i thought wasnt untill i looked on epc and see they go the other way i thought about getting the other one off i mean its a safer way the bolt is need going to fall off as you cant even get it out but my god what a job lol

MBXB
01-28-2008, 11:59 AM
I found that dropping the crossmember made it easier to do the R&R especially when torquing the arms down under load.
It was just easier to get the tools in there.
Still had a ground down wrench though.

Ross
01-28-2008, 12:09 PM
I think a lot of problems occur here because of the kind of wrenches some folks have.
Good quality tools are expensive, large good quality tools are really expensive. The temptation to buy that set of big wrenches from India is great when comparing prices. The problem is those el cheapos get their "strength" from bulk rather than good alloy and accurate machining. These might work just fine on an oil rig but are often bulky enough to be worthless for automotive work.
One more reason not to use crappy tools.