Tri-Link/Rear Upper Control Arm Disconnecting

blaizemarshall

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I've been doing a bit of digging about the rear upper control arm or tri-link. I have seen a lot of posts about installing a new one but not a lot about the experience after it was installed. I figured I would do a small writeup about my experience with this particular part as I recently had a not very fun one.

I was noticing a clunk in the rear as I went over speed bumps that was getting louder by the mile and the shift from reverse to drive was quite harsh and often accompanied with a similar clunk. After some digging around it was found to be the bushings and ball joint in the rear upper control arm. The bushings were torn and the ball joint shot. Due to lack of time and tools I had a transmission shop replace the entire piece with a new one. After getting it installed it felt like a new car (kind of). No more clunks over bumps and shifting smooth. Until one day when I felt like the car was back to its clunky self. Upon a quick roadside inspection I found that the ball joint had completely disconnected itself from the top of the rear differential (Picture attatched to post of what I found). This was pretty frustrating as I just spent upwards of $700 to have it replaced and it left my driveshaft vulnerable to harsh motion from the drive train. Of course this happened over the weekend so the shop was MIA. I decided to give a crack at connecting it on the side of the road and actually got it done with two jack stands and some physics. After a couple of days of driving it was back disconnected! At this point I was kind of concerned that something was wrong with the part on the differential that holds the ball joint. I reattached it and felt much better this time around as it seemed to have go in deeper where the bolt really went through the little groove of the joint (with a little hammering).

Since then I have driven on it quite a bit and it has not come disconnected but it leaves me worrying every day if it will happen again. I was wondering if anyone else had a similar experience with that ball joint dislodging itself or if anyone had advice on how to make sure it doesn't happen again. Sorry for the long post but thanks for reading!
 

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tommudd

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Did you remove the bolt completely before installing the ball joint back down in the bracket ?
If not remove bolt completely then install ball joint down in as far as possible
Then reinstall bolt through and tighten
You can see the groove in the ball joint stem and that is where bolt goes through to hold it in place
If installed correctly then there is no way that it can come apart
doesn't appear it was done right in the first place
 

blaizemarshall

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Did you remove the bolt completely before installing the ball joint back down in the bracket ?
If not remove bolt completely then install ball joint down in as far as possible
Then reinstall bolt through and tighten
You can see the groove in the ball joint stem and that is where bolt goes through to hold it in place
If installed correctly then there is no way that it can come apart
doesn't appear it was done right in the first place
Yeah I dont think the shop did it right and I dont think I did it right the first time either. The second time I removed it completely and ad far as I could tell I got it in the groove. However the bolt dod not slide back in once in place ver easily and some persuasion was needed. Do you think that means it wasnt in all the way or is it just a tight fit?
 

tommudd

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Its a tight fit but you should be able to tell if it is down in all the way and bolt is in right
 

AdamG

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I was just replacing mine and had a different issue, the split opened up more when I inserted the ball joint down and now the bolt won't go all the way through even with the ball joint not seated. Any ideas on how to tighten the split up? I started tapping in the old bolt however it started mashing the threads
 

DadOSix

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I was just replacing mine and had a different issue, the split opened up more when I inserted the ball joint down and now the bolt won't go all the way through even with the ball joint not seated. Any ideas on how to tighten the split up? I started tapping in the old bolt however it started mashing the threads
If you can get at the mount easily, take a pair of channel locks and squeeze it gently by the bolt hold part. I say gently, because these things are very brittle amd snap easily. Only hope for another is a parts yard, as dealer price is over 500 bucks for the mount. No kidding.

Might also use a c-clamp, or vise grip and squeeze that way.
 

blaizemarshall

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I was just replacing mine and had a different issue, the split opened up more when I inserted the ball joint down and now the bolt won't go all the way through even with the ball joint not seated. Any ideas on how to tighten the split up? I started tapping in the old bolt however it started mashing the threads
Possibly if you can fit a c-clamp around the ends and slowly add pressure to it may be enough to squeeze it back. Also it may be a pain but if you can remove your mount it may be easier to adjust off the car in a vise.
 

tommudd

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I was just replacing mine and had a different issue, the split opened up more when I inserted the ball joint down and now the bolt won't go all the way through even with the ball joint not seated. Any ideas on how to tighten the split up? I started tapping in the old bolt however it started mashing the threads
Ball joint has to be completely seated before you can install the bolt
as you can see on the ball joint, there is an area where bolt goes through ( concaved in ) that area has to be down far enough for the bolt to pass through
If the split is bigger than normal then should drop right down in. I never open them up more than stock, no need to to
If you do not have it so bolt will go in completely straight then either raise or lower the front of the diff/ pinion area to let it go down in.
When changing tri- links I always remove the whole bracket and tri link to make it so much more easily to swap out
 
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