New Rear Driveshaft U-Joint Very Tight

Greetings,

Mostly 1999 XJ, 4.0, AX15, 8.25. NP-231 T Case.

I went about replacing my u joints today and as the title suggests, I've got an issue. I used the vise & socket method to get the old ones out. They were in there good but came out without any real trouble. After that I started re-installing the new ones (Spicer 5-153X, 1310s, based off another post). Everything seemed great until I went to install the final retaining clip. It doesn't snap in willingly. I can get it to seat with a hammer/socket or small punch, but it's binding the u joint too much if I do. I'm talking tough to move by hand binding.

Just wondering what you guys think. I really didn't want to go to the forums with this, but it looks like something's off. I've ruled out dislodged bearing rollers and feel fairly confident I have the right u joints. I've tried whacking the ears of the assembled product with a good sized plastic-capped hammer (I work in a bike shop) to no avail.

I'm leaning towards yoke ears being off, but this is my first u joint job. What do you think?

Some other relevant info: As I've mentioned before, I have a Franken-Jeep. It's a 4x4 conversion, meaning a scrapyard driveshaft and all kinds of other mystery.

And if it helps, I'm referring to the u joint between the driveshaft and rear end.

How did you rule out the needle bearings being displaced? It sounds like a classic case of one needle falling to the bottom of the cap. I've done it and it still happens on occasion. The only solution is to start over. I always add a dollop of grease inside each cap to help keep the rollers in place. It's a little messy but it helps.

Whack the ears away from center with a real hammer. Mallet will do nothing. If you can get the snap ring I doubt you dropped a needle. I think you're on the right track, it sounds like the ears are pulled in a little.

trippled said:

If you can get the snap ring I doubt you dropped a needle. I think you're on the right track, it sounds like the ears are pulled in a little.

Click to expand...

This ^^^

Thanks to everybody for the feedback.

Regarding how I know I didn't have a dislodged needle, I disassembled the entire unit (multiple times now) and found all the bearings still in place with no visible signs of damage. Also the tolerance issue I'm having is a lot less than the diameter of one of those needles. The bearing caps seat nicely.

I tried all sorts of hammer tricks today (with a stronger hammer) to no avail. I tried hitting the "shoulders" of the assembled unit, smacking the ears of the disassembled unit, then smacking the ears of the assembled unit, etc. Same results. As a side note, not sure of the technical terms but the bores the u joint presses into on the yoke and the slot for the retaining clips are very clean.

I wish I could feel a proper new u joint install. I kind of wonder if I'm overthinking it. I expected the new components to be a lot tighter than the old ones, and while mine move smoothly they just seem too tight. The force required to swivel the rear u joint in the driveshaft yoke is roughly similar to what it takes to open a tight pickle jar. There's also the issue of having to "force" the final retaining clip (I have to take a small punch and tap it into the reamed out area).

It's tempting to just say screw it and hook it up, but this is my DD and money is tight right now, so I can't afford to have it blow apart going down the highway. So as of now the plan is just to order a new driveshaft and play it safe.

If you can get the clip on I'd bolt up the driveshaft and take it for a ride -- just go a few miles, stay close to home bring tools to remove rear driveshaft just in case -- you can always get home on the front shaft alone

Take it for a ride then check that u joint again, see if it hasn't broken in a little

You're probably going to be just fine

trippled said:

...... I think you're on the right track, it sounds like the ears are pulled in a little.

Click to expand...

I've done the same thing with U-joints. The yoke gets sprung a little during new joint installation. Maybe you can put a spacer between the yoke ears and pry against it with a crowbar, or hammer a wedge between the spacer/yoke to spring the ears back out...

The force required to swivel the rear u joint in the driveshaft yoke is roughly similar to what it takes to open a tight pickle jar.

Click to expand...

That's about how mine felt a month ago when I put it in. (And I don't have super wrist and hand strength.)


I figured they better damn well feel tight at first. The forces they are encountering in operation are far greater than what my wrists can manage.


But what do I know. Haven't done it many times.


Also took me a bit of tapping with hammer and screwdriver to get clip in.

Heavyopp said:

If you can get the clip on I'd bolt up the driveshaft and take it for a ride -- just go a few miles, stay close to home bring tools to remove rear driveshaft just in case -- you can always get home on the front shaft alone

Take it for a ride then check that u joint again, see if it hasn't broken in a little

You're probably going to be just fine

Click to expand...

Maybe I'll give it a try then. It's going to be a week before I can order the new one anyway.

I hooked up the driveshaft last night and have now put several miles on it. Bolts are tight, all clips still in place. I'm going to keep driving it to and from work and maybe pull it back out to inspect over the weekend.

Whatever the case, my original problem (drivetrain vibration) is totally gone and the "clunk" I used to get when shifting into gear has also stopped.

HH-Bham said:

That's about how mine felt a month ago when I put it in. (And I don't have super wrist and hand strength.)


I figured they better damn well feel tight at first. The forces they are encountering in operation are far greater than what my wrists can manage.


But what do I know. Haven't done it many times.


Also took me a bit of tapping with hammer and screwdriver to get clip in.

Click to expand...

If you didn't relieve the joint after installation, it'll fail prematurely. On a free joint, such as the axle end, straddle the caps on something like a vise or a couple of boards and hit the end of the shaft, then flip it and repeat. The caps will seat against the clips and the joint will turn easily.

On the yoke end, you have to relieve it both ways.

Overland said:

If you didn't relieve the joint after installation, it'll fail prematurely. On a free joint, such as the axle end, straddle the caps on something like a vise or a couple of boards and hit the end of the shaft, then flip it and repeat. The caps will seat against the clips and the joint will turn easily.

On the yoke end, you have to relieve it both ways.

Click to expand...

I tried this a few times and unfortunately nothing changed.

Overland said:

If you didn't relieve the joint after installation, it'll fail prematurely. On a free joint, such as the axle end, straddle the caps on something like a vise or a couple of boards and hit the end of the shaft, then flip it and repeat. The caps will seat against the clips and the joint will turn easily.

On the yoke end, you have to relieve it both ways.

Click to expand...

A bit hard to describe without a picture, but I use a piece of u-channel or a couple of blocks when pressing out joints. They go underneath and support the cross of the u-joint, then a big socket goes on top. Pressing or hammering on the socket then forces the ujoint upwards and the cap goes up into the socket. This avoids pressing the ears together and deforming or breaking them.



Going together with a new joint usually requires far less force once you clean and lightly oil the bores. I prefer a clamp or press for installing so you don't knock the needles loose. It also goes together much better and lasts much longer if you haven't gone crazy with the press or a sledge hammer and bent or misaligned the ears.