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whitess
04-02-2010, 07:31 AM
What is the advantage / reason for tightening the rear control arm bolts at ride height / wheels on the ground? What disadvantage is there in tightening them with the wheels off the ground?
Thanks,
Larry.
JohnUlaszek
04-02-2010, 07:47 AM
What is the advantage / reason for tightening the rear control arm bolts at ride height / wheels on the ground? What disadvantage is there in tightening them with the wheels off the ground?
Thanks,
Larry.

What type of bushings are in your control arms?
whitess
04-02-2010, 09:52 AM
The bushings are stock recently replaced with the arms.
JohnUlaszek
04-02-2010, 10:01 AM
The bushings are stock recently replaced with the arms.

Stock rubber bushings are essentially non-linear springs. If you tighten it at full droop you are pre-loading the bushing/spring. If the bond is strong enough between the rubber and the crush sleeve it may ride poorly until crush sleeve to rubber bond lets go, or the crush sleeve rotates.
If you tighten it at ride height it will be able to work within in it's design parameters.

Delrin or Spherical bearings designs are free to rotate so it does not matter when you tighten them.
whitess
04-02-2010, 10:29 AM
John, Thanks very much for the help. My guess is that they were installed at full droop,
which explains a lot about how they are functioning now.
HWYSTR
04-06-2010, 08:06 AM
Rear control arms, right? Doesn't the inner sleeve prevent the bolt from crushing/pre-loading the bushing? From my understanding, the issue is only experienced on front lower control arms?

.
MrQuick
04-06-2010, 09:24 AM
nope, same basic design and same problems will arise.


Vince
HWYSTR
04-06-2010, 10:02 AM
Hm, interesting, will have to go look now! We're talkin' an A-body, right? I recently just switched to the GWs with bearings, so have the old ones out to look at, will have to check (to correct my own thought-process if nothing else!). learn sumpthin' every day! Heh-heh!

.
whitess
04-06-2010, 10:22 AM
Mine's a G Body.
MrQuick
04-06-2010, 10:23 AM
yep, bonded sleeve and shell.

You did good with the GW's, much better at articulation.

G' body is the same, what problems are you having??

Vince
whitess
04-07-2010, 05:50 AM
1. Harsh / Stiff suspension over bumps
2. Rear sits higher on one side than the other
3. The ride height has actually gotten higher on both sides (one side a little more) than it was when the new control arms with bushings (GM) were installed (4000 miles ago), shocks (Bilstein) were installed about 8000 miles ago.
Just the usual stuff.