Why don’t my new U joints fit? (Solved, thanks!)

[Righty Tighty]

Replacing the U joints on the E body, 8.75 rear end. I have the small 7260 joints up front and a universal 7260/7290 at the differential. I ordered Neapco 1-6301 for the front and a Spicer 5-789X universal for the rear.

The cap diameters are correct, but when I go to press them in, the lock ring grooves are too wide apart and I can’t get both sides inside the flange of the shaft to get the lock rings on. The inside diameters on both ends of the shaft are 2.125, and I’m getting almost 2.250 on both new joints. I’ve tried the Moog 347, same measurement.

What’s going on here?

 

[Craig Burriss]

The little rubber boots on them need to be compressed down sometimes.

 

[Alaskan_TA]

And.....

The needle bearings inside the cup can become displaced, jamming them into the bottom of the cup.

You may have to remove the U joint to check that and reposition the needle bearings.

If any came out and any overlapped causing bends, time for another new U-joint.

 

[Righty Tighty]

Thanks, to both. I’ll double check that no bearings moved and I’ll try pressing the caps together a little more. I was worried if I squeezed the caps together too much that the joint would be too tight.

Be right back.

 

[RustyRatRod]

Yeah, the amount that cap needs pressed in is suspiciously close to the width of a needle bearing.

 

[Bad Sport]

I was worried if I squeezed the caps together too much that the joint would be too tight.

I typically press them in and once the clips are on take it out of the vice and give each cap a gentle rap with a hammer, one side and then the other. I don't know if it helps but that what I do, lol. It does seem to make the joint float a little better.

 

[Righty Tighty]

I checked all the caps, no issues there. I removed the fatter clip that I was able to get on and replaced it with thinner clips and was able to get both on. Now where on earth did I even get that thicker clip? Who knows.

That was the universal, now onto the slip yoke. Thanks for the help so far.

 

[4spdragtop]

I've either used a vise or c-clamp to install. Never been successful by hand.
Measure inside to make sure yoke hasnt been squeezed too tight??

 

[Righty Tighty]

I've either used a vise or c-clamp to install. Never been successful by hand.
Measure inside to make sure yoke hasnt been squeezed too tight??

I’m fortunate to have a press here, so that’s what I’m using. At first I did think that I squeezed the yoke and made it too tight, so I measured both ends and they were 2-1/8” exactly.

Well, the slip yoke is done. Just as easy as that! I was being scared and not pressing the joints tightly enough. Easy peasy. Thanks guys!

 

[4spdragtop]

I hear ya with the press. Makes me leery everytime I use it lol. Usually I've scuffed the rust off to help them fit also.
Glad ya got it.

I’m fortunate to have a press here, so that’s what I’m using. At first I did think that I squeezed the yoke and made it too tight, so I measured both ends and they were 2-1/8” exactly.

Well, the slip yoke is done. Just as easy as that! I was being scared and not pressing the joints tightly enough. Easy peasy. Thanks guys!
View attachment 1715896064

 

[RustyRatRod]

Sometimes u joints come with different width clips. Glad you got it figured out! More progress!