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Rear suspension carrier-damaged camber adjust area

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Old 04-14-2012, 09:18 PM
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ammonman
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Default Rear suspension carrier-damaged camber adjust area

I am starting to order parts for my TT/TC and rear suspension refresh. This will also be a big trans refresh as my B3 clutches are just about gone so I might as well do the B2 piston, K1 spring, and primary pump re-seal.

I noticed that the bearing surface for the camber adjustment eccentric flanged bolt is damaged on the passenger side. Looks like someone tried to compensate for worn upper arm bushes by cranking hard on the eccentric bolts. Should I source a good used carrier or will renewing the upper arm bushes be enough to compensate for the crush damage to the adjuster bearing surface? I'll try and post some pics tomorrow.

Thanks

Mike

Last edited by ammonman; 04-14-2012 at 09:51 PM.
Old 04-14-2012, 09:23 PM
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Ducman82
 
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any pictures?
Old 04-14-2012, 09:39 PM
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Bill Ball
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Yeah, pics. The toe adjustment is part of a cast aluminum bearing carrier on the front of the lower control arm. Is that what is damaged? The upper control arm bushings affect camber more than toe. They are usually distorted, making camber more negative so it's hard to get camber into the spec range. I have not seen them cause an issue with toe. They are easy to replace.
Old 04-14-2012, 09:49 PM
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ammonman
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DOH Should be camber adjuster. Original post edited.
Old 04-14-2012, 11:20 PM
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Bill Ball
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What's damaged? Item 6 is the camber eccentric.
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Old 04-14-2012, 11:30 PM
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ammonman
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Whats damaged is the surface on the suspension carrier (Item 1) that the outside diameter of the eccentric flange on the bolt bears on to adjust the bottom of the wheel in and out. Looks like someone was trying to get as much camber as possible to bring the alignment into spec and jammed the eccentric into the aluminum lip on the suspension carrier, cracking and deforming the bearing surface. I'll post a pic tomorrow.
Old 04-15-2012, 12:45 AM
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Mrmerlin
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the usual failure in the lower cross member is the bolt not being torqued to the correct spec.
thus when the car is driven the eccentrics will slide in the slot and damage the walls of the eccentric edges.
refitting new upper control arm bushing will cause the camber to change as the top of the wheel will now be pushed outwards thus the lower adjustment will need to move inwards and the worn edges will usually not be sufficient to make this happen,
the one way to change this is to remove the load from the LCA and then make the adjustment then lower the car and rechek the numbers.
the other way is to replace the lower cross member with a good unit and possible replace the eccentric bolts and eccentrics as well
torque numbers for the rear LCA attach bolt are 140 ft/lbs for camber
the front LCA attach bolts are 82 ft/lbs these control toe
NOTE the front LCA attach bolts are not able to be torqued as the torque wrench wont fit on the nut
Old 04-15-2012, 01:58 AM
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Bill Ball
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Originally Posted by ammonman
Whats damaged is the surface on the suspension carrier (Item 1) that the outside diameter of the eccentric flange on the bolt bears on to adjust the bottom of the wheel in and out. Looks like someone was trying to get as much camber as possible to bring the alignment into spec and jammed the eccentric into the aluminum lip on the suspension carrier, cracking and deforming the bearing surface. I'll post a pic tomorrow.
That, you know, is the crossmember. I'd like to see the damage, and I would try some kind of repair, such as welding up the damage. Also, the damage may not be consequential if you can still lock the camber eccentric. It is quite common not to be able to get the camber to less than -1 degree. Replacing the upper control arm bushings usually helps.
Old 04-15-2012, 01:25 PM
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Mrmerlin
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I have seen a few cars where this was an issue one of them was mine,
after getting a alignment,
when i got home the RR eccentric had chewed out the eccentric wall,
I jacked the car up reset the LCA to where it looked when it was initially adjusted,
I was watching the alignment and re torqued it.
To get things close you can use your eye,
when the car is on the ground and the suspension is settled the rear wheel should be straight up and down its pretty easy to see if its not
Old 04-15-2012, 05:35 PM
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ammonman
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Here's a pic of the damage.
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Old 04-17-2012, 07:16 AM
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ammonman
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Any feedback on the damage in the pic above?
Old 04-17-2012, 09:54 AM
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i would say your good man. replace the bushings, and re install. if it really bothers you, weld it up, or get a new x-member
Old 04-17-2012, 10:32 AM
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ammonman
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The cosmetics don't bother me. Just want to make sure I have enough adjustment after new upper arm bushings are installed.

Thanks
Old 04-17-2012, 10:48 AM
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Ducman82
 
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you should be ok. but you won't really know till alignment time..
Old 04-17-2012, 11:24 AM
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Tom in Austin
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When I changed upper arm bushings I got back about a half a degree of camber on each side. Hope that helps ...


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