New Upper Ball Joint Nut Will Not Tighten

Hi All,

I replaced both ball joints on my 1992 XJ 4.0 4X4 Auto tranny. Replacement seemed to go well. I believe I completely pressed new joints into the yoke. Both seem even with the milled surface on the yoke.

I installed the knuckle and tightened the lower ball joint nut to 75 ft-lb. However when I attempt to tighten the upper nut the stud spins before the taper jams into the knuckle. This happens on both passenger and driver sides.

I shimmed the upper knuckle cone with 0.005" copper foil and can get the nut to tighten. Steering is fairly heavy though and Jeep follows a turn when steering is released rather than comes back to straight ahead. Could be just the parts are new and tight...

Ideas are:

The yoke is too wide (I can see it bend down a little when attempting to tighten)
The ball joint stud is slightly too short.
The knuckle taper is worn (doesn't appear worn though)
Joints are not fully pressed into the yoke.

With respect to not fully pressed in, there are flats milled on the yoke. The joint shoulders seem flush with these flats. Possibly there is a counter-bore that I can't see?

Any other ideas will be appreciated.

Did you check the taper(s) while you had everything apart?

Check tapers... no I did not. I purchased the ball joints as a part of a steering kit containing the sway bar, tie rod ends and bar to the pitman arm. Basically all the steering linkage and ends. All these were a perfect match to what was on the Jeep so I didn't think to try the ball studs in the knuckle. Good suggestion though. I expect to take one side at least back off for further inspection and I'll have a close look at fit.

Thanks!

Putting a jack under the knuckle and lifting until the stud grabbed worked for me. The one didn't take much, the other got a bit hairy...

The jack is a great idea! Thanks. I'll try this if I end up pulling the knuckle for further inspection.

After your ball joint replacements did steering feel heavy? Did this go away?

Mike

Mine were noticably tighter but no so tight that they couldn't be moved by hand without too much force. On the road, they did feel tighter for a day or so but I either got used to it or they loosened up. Dana OEM replacements in my case...

My joints are really tight. I can move them by hand but it takes both hands.

Tighten the top first. Check the lower ball joint seat and see if it is the adjustable type (split ring) or not. I forget which year they did away with the adjustable bottom seat. *If* it has the depth adjuster (split ring) it may have moved and may be part of your issue.

"Tighten the top first..." sorry the bottom joint holds the knuckle down so it seems to me that the bottom must be tightened first, thereby raising the knuckle along the bottom ball joint taper. This -should- have the effect of lifting the knuckle towards the top. Maybe there's something I'm not seeing?

"Adjustable or not" Thanks! There's a Youtube video that mentions the adjustable seat. I looked over my knuckle generally and thought I did NOT see a seat. But then I started wondering. It is good to know that there are years where the seat was not adjustable. Now I can trust myself. I believe my knuckle had no adjustable seat. My '88 FSM describes this seat but my present Jeep is a '92 so sometime between '88 and '92 they stopped the adjustable seat.