Stripped threads on upper control arm ball joint socket

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PikaPhantom

PikaPhantom

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Hey guys so the threads on the upper control arm ball joint got stripped when I was torquing in the ball joint. Just wondering what my options were in terms of fixes or if it’s just best if I go out and buy a new control arm with everything ready to go.

thank you

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Install the ball joint and tighten it until right before it strips and put four GOOD spot welds on it. People have done it for decades. Or of course, a new control arm.
 
They are famous for doing that. Tack weld the ball joint in. It doesnt need a complete weld. A few really good tacks.
 
Eventually you’re just going to have to replace it. They make reproductions at the moment, so it wouldn’t be the worst idea to just replace it. It’s already apart.

Or tack weld it in place and replace it next time, but who knows what they’ll cost then or if they’ll still be available.
 
The large ball joint UCAs are reproduced. Are the small ball joint ones being made too?
If not, the OPs options are limited.
I'd have no problem with even running a bead of weld around the entire rim of the ball joint.
If you want to just go the easy way.... Replacement UCAs in the small ball joint size are still easy to find.
 
I vote for welding four spots only in case you have to put new ones in again in the future. If you can only buy used UCAs you might be in the same boat with stripped threads again.
 
I agree with tacking them. Do not overheat. New ball joints have plastic ups.
Who is reproducing them? Where can you get them?
 
The threads are supposed to look kind of funky as they are like self-locking, the real test is to install the ball joint and torque it to whatever the spec is large and small are different, if the joint seats against the arm and can be torqued to that spec they are good.
 
Tack it and move on.
The new ball joint will probably last longer than we would like to admit.
 
One other thing is this. IF you do find a reproduction, which I did not after 20 minutes and gave up, it likely will NOT be threaded in the ball joint hole. The original ones were not threaded, either, because the ball joints cut their threads as they install, so if the control arms are not threaded, that's why.
 
never had any threads to start with,
and the balljoint only has the mearest hint to get it to work its way in

Don't worry just start new joint in with arm in vice, use a rubber mallet to tap it down to the start of the thread. Once started and straight
fit arm to car to finish the job with a big bar.
if you end up not thinking enough effort was used to get it in you can wind it out and get a different arm...BUT its usually exceedingly hard work....

wind it in till the top section, the head of the joint, hits the pressed section in the arm you don't need to go much further you will be at torque spec, you are not doing a NUT up tight in the normal sense, you know what tight feels like and it should have been tight from the get-go, shallow thread in balljoint is cutting new ridges into the pressed arm...thats near tight enough with one last nip up at the end
the thread is for installation, its not there to be under tension like the thread on a head stud is , the joint is basically held in by the friction between arm and balljoint case. Torque setting in book was to stop "strong men" at the local alignment place from ruining arms

job done.

if its loose and takes no effort you have a problem, somone has over tightend the previous joint, or put it in very crooked . if its not loose for any of its journey IN, it aint going anywhere.
The balljoint would have to seize solid to wind it out
or the upper ARM would need to jam to punch it out
both in standard working form, move easily in comparison to the force necessary to knock out the top joint.

other option is to use a cone or socket in a press to gently reform/close up slightly the pressed section of the arm. go too far and you can't get the joint in.

make sure you replace both lower and upper bump stop rubbers to avoid binding joints at full travel in either direction and do up all "Bushing Bolts " at ride height with the car on its wheels.... at rest, all bushings includeing steering idler should be in relaxed not twisted position.

PS sure you need to change them.....? its the bottom joints that take a battering

Dave
 
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Here is a old schoot trick I have used. Take some steel stock like in a feeler guage. .005 is what I have used. Put it in place slowly tighten the ball joint in it will shape the shim stock into the threads and almost be like new. We did it all the time in the 80's and not one fail.
 
Out of the box, if you're uneasy about welding and overheating the bj, ya' might consider refurbishing the a-arm hole. The bj should cut new threads. The trick would be keeping it straight.
 
Oldmanmopar said:
I agree with tacking them. Do not overheat. New ball joints have plastic ups.
Who is reproducing them? Where can you get them?
Click to expand...
I got uppers from Amazon for my 72 Scamp, no problem. But lowers were a different story. Left side lower I got from Amazon but they were outa stock for the right side. So, I ordered from Rockauto and they sent me the wrong right side lower twice. They were real good about sending me a refund after that. Anyhow, after waisting about a month with that, the right side lower was back in stock on Amazon so I got that and the car is a way different animal with all new ball joints in it.
 
You can get a new ball joint sleeve, and just replace the threaded part, without replacing the whole control arm.
 
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