Upper Rear Control Arm - stuck replacement

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JBDive

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Tried to replace the upper arm today and things went so so. I got the old arm out really quickly and was feeling great about my progress then got stuck putting the new arm back in. Had to take a break for the afternoon to do something else then on getting back to the job I was able to get it mounted and inserted into the retention hole, almost. I am stuck with the ball joint needing to drop maybe a 1/4 inch more. I've bounced the rear end around, dropped the entire body back down but no go. After a very long day of multiple tasks I just bailed for dinner to take this up tomorrow.

So what is the trick for that last 1/4 inch? I am tempted to start the car up and move it into Drive and Reverse a couple of times to see if that will rock it into place and if not that just pull out the drive way and let the curb bounce maybe do it. Ideas?
 

duderz7

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Try jacking under the pinion flange, sometimes a little rotation is all that is needed. I think many folks here have luck with getting ball joint set then bolting bracket to axel.
 

JBDive

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Yeah we have rocked the diff a good bit placing a jack with board under various locations to swing it back and forth. I really only gave it about 30 minutes of screwing around with it before calling it for the night as I spent most of the day on another task and was beat up. Going to start over again tomorrow doing that rock and rolling. I've got the wings bolted in, not too tight but there is next to no movement once they are bolted in I don't think tight or loose makes a diff.
 

DadOSix

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Try jacking under the pinion flange, sometimes a little rotation is all that is needed. I think many folks here have luck with getting ball joint set then bolting bracket to axel.
This is how I go at it now. It is IMO easier to get the ball joint into the bracket, then mount it to the diff.

My usual is not to pull the tires and shocks. The back goes up on ramps and I work under from that. It is a bit tight, but I can always get the UCA out the drivers side. Since not much travels and drops, I have less to re-align. I guess if I had a lift, I would do it the right way, but on the ground is how I go. A bit of a bottle jack on the yoke is about all I do to get the bracket (joint attached) back onto the diff.
 

JBDive

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Got it. Found a video that suggested using a ratcheting strap to wrap around diff and upper control arm, tighten then use jack under diff. Had just that last quarter inch to go and what do you know, slap on the strap, placed a board under differential, towards the front half so as I rose it up it tilted slightly back and with the added pull of the strap it popped right in.

Job is really pretty easy, multiple jacks makes it much easier. Just follow the Youtube videos for removing the arm, no need to take anything extra off, just the two bolts on the wings then the center retention bolt. Raise the car so tires are off ground about 3 inches, put a jack under the diff (use wood block) to support it. Remove the bolts, (ratcheting 15mm wrench very helpful), bend the heat shield by the muffler all the way down, slowly lower differential, it should just release. If it doesn't, put a chisel in the compression slit to open just a bit (careful), play with angle you are trying to get diff to lower at by placing the jack further forward or rearward as it will allow the whole axle to twist/rotate. CAREFUL - no need to drop it all the way down and have your springs go flying or falling out. Pretty much repeat the process to replace until you get it centered and somewhat into the center retention hole then use a ratchet strap to pull it down and you raise the diff and it will likely just pop right in.

If everything goes as expected, 1.5 hours. Results - your ass end stops swaying every time a truck passes you on the highway and that thunk you hear going over speed bumps will stop.
 

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