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Do these upper a-arm ball joint threads look OK?

AR67GTX

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I got nominated to press a friends new bushings and install new ball joints in these upper a-arm from a Challenger by virtue of having a 12 ton hydraulic press, a set of Mopar suspension tools and having rebuilt the front and rear suspensions on my 67.

When I got home with them and looked them over I became concerned by the ball joint threads. Other than the first 3 or 4 starter threads, they are barely there. I don’t remember my 67 a-arms having threads that short and shallow.

But from memory, the ball joint threads are tapered and on the ball joint itself, are self-cutting threads that cut into the a-arm. So it may be these arms have never had more than the original ball joints cut into them and the new ball joints will cut deeper and longer threads into the a-arm when torqued.

What say the more experienced front end members - look OK or not? I’ve told him I won’t be able to get these things fully torqued in my vice as it will pull my bench over - we‘ll have to finish them up mounted in the body.

IMG_1543.jpeg
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Look usable. If the arms are in good shape otherwise, crank the new ball joint in and see if it'll torque to spec. If it gives, welded it with 3 or 4 spots.
 
Just make sure you start the ball joint in square with the threads. Even new one arms look like puke to me....that is if you can find a new one anymore.
 
They look fine, they don’t look like normal threads on a bolt.

Yes make sure to start it straight.
 
They also kind of sel tap in my experience. double check them ON THE CAR!
 
They also kind of sel tap in my experience. double check them ON THE CAR!
They are an interference fit for sure and will roll metal if too tight and in years past, I found some aftermarket replacements that did just that but, if they are from China, they will most likely be loose. Heck, have even had some where my ball joint socket didn't even fit!!
 
They are an interference fit for sure and will roll metal if too tight and in years past, I found some aftermarket replacements that did just that but, if they are from China, they will most likely be loose. Heck, have even had some where my ball joint socket didn't even fit!!
a few, then came out the big *** channel lock or the three foot pipe wrench! There are two different size sockets also I believe.
 
a few, then came out the big *** channel lock or the three foot pipe wrench! There are two different size sockets also I believe.
Gotta be a little careful with the big guns as you can tweak the arm...that is if the vise and vise mount is strong enough to hold it.
 
Gotta be a little careful with the big guns as you can tweak the arm...that is if the vise and vise mount is strong enough to hold it.
LOL thats funny right there. Dont let the vice hit your feet now!:BangHead:
 
Yes metal can come out when installing the joint, kinda goes with the territory.

yes there are 3 sizes of BJ sockets For mopars.
 
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Just A here mostly. The tiny one!
I've had a couple of A's but it's been a very long time ago. My first one was 67 Dart....dropped in a 225 with a completely rebuilt K frame and 3 sp (car was an original 273 with a missing trans) and stuck in an 8 3/4 w/3.91 gears, added a straight pipe, jetted up the Holley, advanced the timing.....etc etc and that thing ran pretty good. Could hang with stock 350 Chevy's of the mid 70's and the occasional 289 Ferd but the 304 Gremmies.....forget it lol
 
Yes mental can come out when installing the joint, kinda goes with the territory.

yes there are 3 sizes of BJ sockets For mopars.
Generally, I go 'mental' when I have to do a front end! lol
 
They are NOT self tapping.

The threads are very shallow with a curved profile vs a traditional pointed profile.

If you can't get a full or almost full turn in by hand- something is wrong.
They are easy to cross-thread.

If you can thread them all the way in by hand- something is wrong.
It's easy to crack the control arm.
 
Part of my concern was the threads that do exist are not very clean in areas - clean as in consistent and uniform. I thought there might be some paint globs or grease in them but I cleaned one with a brass brush and acetone and it just appears to be just rough metal in the threads. The pictures I took above didn‘t focus on these areas very well. He got the ball joints and bushings this week and I’ll pick them up this weekend and see how they fit.

thanks.
 
NEW, upper control arms never have threads in them.
They are manufactured bare, smooth.
The ball joint, to be inserted in the UCA, cuts the threads.
Then forever, and ever, that control arm will have the "threads" that a replacement ball joint should follow, in tightening down.
If not, just tack weld the ball joint, to the arm, in 3 or 4 spots, and your done.
Easy, peasy.

UCA's New (Small).jpg
 
IDK how it cuts threads with those shallow, rounded OEM threads.

Since the OP's threads are "clean", try threading by hand and see how far they go.
A little penetrating oil (or even cutting oil) can't hurt.

One pic does seem to show some questionable areas where the treads look possibly damaged, or maybe the metal is lower than the threads.
 
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