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Ball joint pre-load screw

mgb0302

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Joined
Jun 29, 2002
Messages
424
UPDATE - WELL CRAP!! After 50/50 advice of “leave it” vs “get it out,” I got the old threaded pre-load screw out. However, in the process I boogered up the top threads on the C and can’t get the new screw in. Anyone know the size of the hole and thread pitch? And where to get a thread tap to fix it?
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Can I re-use the old pre-load screw when replacing ball joints?

I am replacing balljoints (D44). I cant seem to get the old pre-load screw out of the inner C. I has soaked it in lube (PB Blaster and WD-40) and heated with torch but it wont come out. One problem is the spanner tool I have - it is brand new but it does not "lock" into place and just slides out when I put any sort of force on the wrench. I'll keep trying to remove it but I'm curious if I can just re-use. I know one way to find out is to install knuckle and hope I achieve the desired pull force on the knuckle, but I'd like to know for sure before I do that. Anyone??
 
Last edited:

Yeller

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You can reuse it, but it has to be free to properly install the ball joints. If it is not free, you cannot properly preload the ball joints and they will more than likely promptly fail. There is also a high potential for it inducing handling issues, the steering being "sticky" and not self-centering if the preload is too tight or, death wabble if too loose. Both of those issues can be serious safety problems.

A few tips, strike the outside of the hole with a hammer, it will help loosen the rust holding it in place. More heat, getting it to the point it is beginning to glow is not too hot, not much more than that but it is not too much. I should expand on that; the heat needs to be focused on the C not the inside of the hole. The idea is to expand the outside, soften the rust and be able to unscrew the insert. The reason the tool isn't staying in has as much to do with the insert as the tool, probably more, probably damaged from previous repairs. I heat them dark red and unscrew the insert if striking the outside of it does not free it up.

When reinstalling don't be bashful with anti-seize to prevent future issues.
 

Yeller

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You are welcome! I've worked on some pretty crusty axles and have never had one that I couldn't get out. If really stuck, heat is your friend.
 

EPB72

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A lot of times going in the tightening/ clockwise rotation first just enough to crack it loose then go counterclockwise wise may help , it does 9 times out of 10 on exhaust fasteners
 
OP
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mgb0302

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Jun 29, 2002
Messages
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I’ve got myself into a pickle!! See new update in original post.
 

DirtDonk

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Well, bummer!
No idea what the thread is, although I think I’ve seen it post to be before.
Is there any way to get in there with a thread repair bar? Might just need to knock down some rough spots? Or are some of the threads really buggered?

And so others can avoid your same pitfall, what did you use to get the old one out? And what exactly was the step that messed up the threads, do you think?
 
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mgb0302

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Joined
Jun 29, 2002
Messages
424
After plenty of heat and overnight soak of PB Blaster I went to work. The thread got boogered when I tried to turn the screw by putting an air hammer on the castle portion of the screw in hopes the force would shock it loose. I didn’t notice that part of the air gun was hitting the top row of threads, which is what jacked up the threads.

Eventually, I used a jig saw and was able to cut out small sections of the screw, a little at a time.

I think I found the tap size by another post on here. 1 1/8 x NF 12. Ordered on Amazon.

Will update next weekend.
 

Oldtimer

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UPDATE - WELL CRAP!! After 50/50 advice of “leave it” vs “get it out,” I got the old threaded pre-load screw out. However, in the process I boogered up the top threads on the C and can’t get the new screw in. Anyone know the size of the hole and thread pitch? And where to get a thread tap to fix it?

The threads in the C are 1-1/8"-12, and go all the way thru.
Now that you have the C completely dissasembled you may be able to chase the threads from the bottom up thru the top with a bolt or a pre-load collar from a new ball joint assembly.

I see taps available on Amazon for less than $50, with a one week delivery.
May be able to pick one up locally at a machine shop supplier.
 

DirtDonk

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Since it’s not really a tapered thread, thankfully, you should be able to start the tap from the underside where the threads are theoretically in good shape, and run it straight out the top.
 

DirtDonk

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That’s another idea! Since these threaded sleeves actually have a notch cut in them, they would act as a thread chaser right there. Have you tried that yet with the new collars?
The notch would be a good cleaner. We do that with spark plug threads all the time.
 
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