Is My Control Arm Toast?

Dylan Galvin

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Left side upper ball joint thread in just fine by hand initially, I cant even get it started on the right. A turn of the wrench is very hard and I'm assuming its cross threading. I got a picture of what I think is the culprit. The top thread gets basically cut off and flattened. Is it time for a new UCA, or should I just wrench it in? Dosent feel right to wrench it, and dosent look truly square.

20191220_123536.jpg
 
Maybe you could thread the ball joint it in from the bottom and straighten it out? Otherwise, good luck finding a tap for that size!
 
A couple of options. You could look for a thread dressing tool and try that or if you are adventurous take a die grinder with a very thin cutting disc and lightly clean it up.
 
I see a new control arm in your future.
2043EB04-7613-4092-B2EE-B320FD3EA6A9.jpeg

I had a similar experience and by the time I got it cleaned up and the ball joint to seat it was also pretty well stripped out and would not tighten, it just spun. It took a lot of effort to spin it but did just spin. I ended up tack welding it which worked until I found a good used assembly with an original ball joint already in it. That was a win win situation as even the best new ball joints are nowhere near as good as originals.
 
Hmmm. Thanks for the tips. I'll try threading upside down, if that dosent work then I'll probably just look into a new arm.
 
I've experienced the same issue. I got a thread chase and was able to clean up the threads. If you could go to a machine shop they would have the correct tool. You should be able to rent it (I'm not big into borrowing stuff). Be cheaper than buying for a one time use.
 
Maybe you could thread the ball joint it in from the bottom and straighten it out? Otherwise, good luck finding a tap for that size!
Upper control arms are not "tapped" so to speak, so what your thinking of a conventional tap isn't used.
Threads on a ball joint are "self cutting" into the metal of the control arm.
If you ever have seen a brand spanking new control arm, from any of the Mopar body style cars, there are no threads in them.
The ball joint itself cuts the threads in the arm.

Now in your case, start the replacement ball joint into the boogered up threads as straight as can be, tighten it down, and if it doesn't tighten down great, you just tack weld it to the UCA in three or four spots, around the joint.

A repair like that has been done forever.
The ball joint ain't going anywhere after the tack weld job.

You are using the correct size upper ball joint socket, or using a pipe wrench, or something, in the removal, and replacement, of the ball joint?

FYI
If you get another used arm, your most likely going to be in the same situation, in removing the ball joint from that arm, and then installing a new one in that arm.
So pick your poison, in which way to want to tackle your present problem.

Ball joint socket.jpg


UCA's New.jpg
 
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Upper control arms are not "tapped" so to speak, so what your thinking of a conventional tap isn't used.
Threads on a ball joint are "self cutting" into the metal of the control arm.
If you ever have seen a brand spanking new control arm, from any of the Mopar body style cars, there are no threads in them.
The ball joint itself cuts the threads in the arm.

Now in your case, start the replacement ball joint into the boogered up threads as straight as can be, tighten it down, and if it doesn't tighten down great, you just tack weld it to the UCA in three or four spots, around the joint.

A repair like that has been done forever.
The ball joint ain't going anywhere after the tack weld job.

You are using the correct size upper ball joint socket, or using a pipe wrench, or something, in the removal, and replacement, of the ball joint?

FYI
If you get another used arm, your most likely going to be in the same situation, in removing the ball joint from that arm, and then installing a new one in that arm.
So pick your poison, in which way to want to tackle your present problem.

View attachment 338494
I wasnt aware they cut their own threads, I'll have to give it a shot tonight. If that dosent work I'll definitely be looking at a new arm since I cant weld. My highschool shop class is bound together with some other nonsense class so unfortunately I haven't learned to weld yet.
 
Wow, "high school shop class"?
Then, i doubt a regular welding shop wouldn't charge you much, if you figured in, what another replacement arm would cost you.

I clicked onto your "profile" and you listed your age at 15.
Your into these old land yachts? :thumbsup:
 
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Wow, "high school shop class"?
Then, i doubt a regular welding shop wouldn't charge you much, if you figured in, what another replacement arm would cost you.
Oh yeah, I should look into that before another arm. It would be nice to preserve the arm as well, even though I cant be certain it's original.
 
I clicked onto your "profile" and you listed your age at 15.
Your into these old land yachts? :thumbsup:
Sure am. The concept of an 18ft cruiser paired with stupid power and displacement and zero regard toward emissions is a beautiful escape from the modern car market. Love em
 
When new, those control arms (or suspension arms) were smooth wall. The ball joint has quite shallow threads that displace the metal (rather than "cutting") when screwed in. Getting the joint screwing in straight is quite important (imagine). There are sockets available for just that purpose as in the socket fits the flats on the ball joint. When doing this, just take your time. Be patient and slow. You will get much better results. Use a long strong pipe of an appropriate size on a ratchet handle (I know, you are not supposed to do that).
Some sockets such as Sunex 10213 or 10214 (depending on ball joint size)are about the lowest price ones available. Also available is PowerBuilt Kit # 32. One source is ebay.
The flange on the ball joint should contact the wall of the control arm. Most ball joints require a minimum torque of 125 lb/ft (or ft/lb). Get a torque wrench if you don't have one. Sometimes the arms do get reamed out due to multiple ball joint changes or whatever. There are companies that have available threaded tube sections that can be installed in a control arm (trimming and welding required). lefthanderchassis dot com, victorypp dot com, stockcarproducts dot com (if they are still around). There is stuff out there to help keep things repairable. It seems most people don't find them for whatever reason.
Your arm may be still useable. Yes, it may take a lot of effort to install the joint. Having the arm still mounted to the car sometimes makes it a lot easier to r and r the ball joint.
There are other tools that would make it a lot easier to r and r bushings in the arms also. Another note, ball joints that look like they have threads are screw-in, ones that look like they are smooth-sided are press-in. Don't confuse the two.
 
I was able to thread the ball joint into the arm, but not without using around 150 ft lbs of force. I assume that's fine, as the FSM says 125 is the minimum. Now I've gotta deal with a stubborn grease fitting, how fun. The Monaco should be back on its wheels tomorrow. Then it needs an engine...

Thanks for spreading the knowledge gentlemen!
 
speedway sells the control arm bushing (real name ball joint sleeve) to guys that build their own----and yes i have bought a few and they have threads---also jegs carries the item----ball joint sleeves------they sell a qa1 press in sleeve that has threads---i welded them into place-----off road racers and suspension builders use them all the time.....
 
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Not uncommon to see many Mopars including C's have the ball joints tack welded on to the UCA's.
Dodge trucks,B series vans,F/M/J bodies,you name it.
 
I wouldn't worry about it, I can't remember how hard they were to reinstall, I just lined up the threads as best I could and tightened them up.

Here's what I started with.

IMAG1625.jpg


Dirty, huh? I just used a screwdriver and some brake cleaner and that was it. Wiped down with a rag and went to the shop to use their vise (there's a pretty cool shop that lets you borrow their tools if they know you, and use a couple items like the press) and a long bar. I didn't weld the ball joint, and I don't have any issues. No go find an engine!
 
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