Upper ball joint nut is stuck to the bolt

[typicalmillenial]

I am trying to replace both front upper control arms, somewhat following this guide but the nut is rusted to the ball joint, trying to loosen it just turns the ball.

This video shows the problem exactly:

I don't have a torch like the video recommends. I plan to buy both a nut splitter and an angle grinder tomorrow and will see what works. Any thoughts / input? Wish me luck!


fwiw it's an 03 explorer XLT

 

[lincolnshibuya]

a MAP torch will do, you could buy it in lowes or home depot.
I'd use a grinder or cutting disc to remove that nut first and use a pittman arm to push the ball joint out (no need for MAP torch)

 

[typicalmillenial]

Well the kobalt nut splitter mangled it but didn't crack it. It's truly a piece of junk.
The MAP torch deformed it some but not enough. Saw a youtube vid that tested the torch against steel and he didn't get very far either.
I was supposed to have my new angle grinder ready but I didn't know dewalt makes different batteries for drills and grinders so I was SOL. I will have to try again another day. The good news is I was able to replace the other control arm because that nut wasn't rusted onto the bolt. The pittman puller got the knuckle off so thanks for that tip.

Funny enough when I put that new control arm in, the brand new nut that it came with did the same thing. It was turning the ball before it was even halfway across the threads! I was able to tighten with a wrench on the hex rod below the threads, but I wasn't able to use my torque wrench and I wonder if it's common to have to destroy the nut to get it off.

 

[shucker1]

Some times when I am putting a control arm back together and the ball starts to "Spin" I'll put a jack under the lower control arm and apply slight upward pressure. Then a few small hits with a 3 Lb hammer on the top control arm will help "Seat" the top taper stud back into the steering knuckle. No need to fight it back together with 2 wrenches. Also a little dab of grease on the threads only helps out.

 

[XploX]

If you were unable to torque the nut, the ball joint isn't seated in the knuckle. Did you look at the taper to ensure it isn't damaged? I've seen the taper elongated and others that were distorted out of round.
A new ball joint should thread together without any issue.
If you have a cold chisel, you can drive it between the notches on the castle nut and it will split it. Go from the bottom of the nut, not the side. This uses the wedging action of the chisel to spread the nut, while it cuts into it.

 

[IndianaKenny]

I just changed both upper ball joints in my '03. If you're changing the control arm, as a last resort, just sawzall the ball joint about 1/2" above the knuckle, remove the rest of the control arm, and them beat the remaining ball joint "stub", downward. It should pop out. Your new control arm will already have a new upper ball joint in it anyways, so it's not like you'll reuse the ball joint anyway.

 

[typicalmillenial]

Shocker and xplox goddamn I wish I knew about the taper stud I will have to check when I get home. Knowing that would have saved me so much time...

There isn't a castle nut on mine just a regular locking with a flange but I might be able to wedge into the cuts made by that POS nut splitter. Everytime while cutting it would start to walk downward, never getting a a good cut from top to bottom

Kenny I was planning to use an angle grinder instead of a sawzall but I think if I cut above the knuckle the stub will be too thick to fit. I'll cut the nut off below it and then use my pittman puller.

 

[typicalmillenial]

So the taper stud doesn't have any hard edges right? I assume it locks to the knuckle just by full contact on all that surface area?

 

[Number Twelve]

I assume it locks to the knuckle just by full contact on all that surface area?

Yep. There are several machines that work by taper fit, like my 1938 drill press and some mills...maybe CNC machines. A slight interference fit on a long taper will hold against incredible amounts of force.

 

[typicalmillenial]

Yep. There are several machines that work by taper fit, like my 1938 drill press and some mills...maybe CNC machines. A slight interference fit on a long taper will hold against incredible amounts of force.

I found this article about taper fits and I'm left with the impression that any improper handling of the ball joint removal can damage the taper and cause other problems. But it also said ford uses non standard tapers. Is there a chance I damaged the taper in my knuckle by banging on it and torching the nut? (EDIT: and for the new arm on the other side, did I damage it by driving it a couple days with the taper apparently unseated?)

 

[IndianaKenny]

Shocker and xplox goddamn I wish I knew about the taper stud I will have to check when I get home. Knowing that would have saved me so much time...

There isn't a castle nut on mine just a regular locking with a flange but I might be able to wedge into the cuts made by that POS nut splitter. Everytime while cutting it would start to walk downward, never getting a a good cut from top to bottom

Kenny I was planning to use an angle grinder instead of a sawzall but I think if I cut above the knuckle the stub will be too thick to fit. I'll cut the nut off below it and then use my pittman puller.

Typical, I just realized I told you wrong!!! As that last resort, you'll need to use the angle grinder to shave off the nut, as close to the knuckle as possible. The ball joint is tapered, with a wide diameter at the top of the ball joint stud, and smaller diameter at the nut side of the ball joint stud. You can then beat the remaining stud upward, to dislodge the remaining tapered stud portion. BE CAREFUL, because any second, after you cut the nut/stud off, the knuckle and lower control arm will be wanting to drop downward, forcefully, (probably when you least expect it, AND when you have a finger in the wrong place).

 

[swshawaii]

Some good pics of the upper ball joint tapered stud removed from the spindle.

How To: Replacing Upper Ball Joints on a 3rd Gen 4x4 [Pictures] | Ford Explorer and Ford Ranger Forums - Serious Explorations

 

[typicalmillenial]

Alright lads after much trouble I got her done with the cutoff saw. The arm popped right out after that. I definitely recommend that route, used a 5" grinder disc with a depressed center. I uploaded pictures onto imgur here. I later had trouble with one of the 21mm nuts in the back. The threads were galled and it took so much torque to get it off that I bent that special washer. Took me about 15 min with a big pair of pliers to bend it back to shape so it would fit.

And a note about seating the taper on the new ball joints. I tried lifting the lower arm with a jack and hammering the upper arm to seat the taper into the knuckle, but as soon as I started turning the locknut the taper would unseat itself and start spinning. You could use a small wrench on the hex rod at the end of the threads to keep it from spinning and twist the locknut up with another wrench which will pull the taper down into the knuckle. What I did was used a small C-clamp to clamp the top of the control arm to the knuckle and keep it seated. Maybe if you tighten the bushings the control arm will be too tight to move up but I didn't want to have to tighten, then loosen, then tighten the bushings again to bring it to the correct ride position.

Thank you everyone for your advice.