Install axle u-joints with or without lube on press fit surfaces?

[maxbraketorque]

I've been watching a bunch of videos on axle u-joint removal and installation. Old u-joints are out, and new are ready to be installed after I finish a bit of clean-up and painting.

Most people put some sort of lube on the press-fit surfaces, but I came across a thread where a person adamantly stated that no lube should be used because it will cause the joint to slip in the press-fit surface during use. Anyone know the correct answer?

[JonnyCat63]

I use some sort of lube on almost everything. Grease, anti-seize, lock-tite, dielectric grease, silicone grease, you name it.

On any metal threads or metal to metal contact, cars, plumbing, whatever, I use some sort of lube. For me, it aids in wear, and make the replacement process much easier.

I can remember years ago snapping a bolt off on one of my Ford vans alternator bolt. A steel bolt into an aluminum bracket, from the factory, no anti seize. Who thought that was a good idea?

I say yes, lube on everything, properly cleaned, torqued and/or assembled, never had any issues.

To quote and old Frank's Red Hot Sauce slogan: "I put that shit on everything!"

[RCP Phx]

Where would it "slip" to???

[maxbraketorque]

Originally Posted by RCP Phx

Where would it "slip" to???

I suppose the inference was that it would stress the c-clips. But I can only guess.

[lawsoncl]

Originally Posted by maxbraketorque

I've been watching a bunch of videos on axle u-joint removal and installation. Old u-joints are out, and new are ready to be installed after I finish a bit of clean-up and painting.

Most people put some sort of lube on the press-fit surfaces, but I came across a thread where a person adamantly stated that no lube should be used because it will cause the joint to slip in the press-fit surface during use. Anyone know the correct answer?

Personally, I clean up the bores with a little steel wool and apply a little oil or antiseize so go in easier and don't get stuck the next time. The only force on the caps is to push the outward, and the clips will hold them. In fact, when you're done, give the u-joint a few taps in either direction to make sure the caps are pushed up against the clips.

[maxbraketorque]

Thanks everyone. I filed off burrs and cleaned up the bores with a wire brush attachment on my drill. It looks very nice now. I'm a big fan of anti-seize as well, so I'll use a bit of that on the bores when I install the u-joints. Hopefully everything will go together without a hitch.

[Unclewolverine]

I've always put them in dry and never had an issue.

[Anak]

I just clean up the driveshaft/yoke surfaces and install the caps with whatever lube/protective coating is on them already.

[Rob Mayercik]

Originally Posted by maxbraketorque

I suppose the inference was that it would stress the c-clips. But I can only guess.

More likely it's because the lube could cause the whole cap to rotate with the joint (and, coincidentally, wearing the holes in the yoke) rather than the friction between cap and yoke holding the cap stationary while the joint rotates in/with the needle bearings inside the cap.

That said, it doesn't sound like most folks have that much difficulty getting those apart - it's not like the joint and yoke are different metals (leading to the galvanic corrosion/dissimilar metals issue that Jonny ran into with that Ford alternator).

[maxbraketorque]

Originally Posted by Rob Mayercik

More likely it's because the lube could cause the whole cap to rotate with the joint (and, coincidentally, wearing the holes in the yoke) rather than the friction between cap and yoke holding the cap stationary while the joint rotates in/with the needle bearings inside the cap.

That said, it doesn't sound like most folks have that much difficulty getting those apart - it's not like the joint and yoke are different metals (leading to the galvanic corrosion/dissimilar metals issue that Jonny ran into with that Ford alternator).

Seems like the u-joint bearing would have to be seized for there to be enough torque to cause the cap to rotate in the yoke.

[lawsoncl]

Originally Posted by Rob Mayercik

That said, it doesn't sound like most folks have that much difficulty getting those apart.

I've done my fair share where the caps are rusted up and a bugger to get out. Some people manage to bend the ears trying to press them out (with poor technique in my opinion). If you break one while offroading, you'll be glad the previous installer used anti-seize.

[Anak]

Originally Posted by lawsoncl

I've done my fair share where the caps are rusted up and a bugger to get out. Some people manage to bend the ears trying to press them out (with poor technique in my opinion). If you break one while offroading, you'll be glad the previous installer used anti-seize.

That is a good argument for the use of anti-seize.

[maxbraketorque]

Originally Posted by lawsoncl

I've done my fair share where the caps are rusted up and a bugger to get out. Some people manage to bend the ears trying to press them out (with poor technique in my opinion). If you break one while offroading, you'll be glad the previous installer used anti-seize.

I used a shop press, and a few of my u-joints took some effort to start moving. A BFH might start things moving more easily, but generally dislike the idea of that approach.

Anyhow, I'm going to use some anti-seize. I can't see how a cap can ever spin in a yoke, and I figure that a bit of anti-seize will help with straightening the ears with a hammer tap after pressing in the caps.

[lawsoncl]

Originally Posted by maxbraketorque

straightening the ears

Expanding on my comment on poor pressing technique:

I use a slightly different method for pressing or hammering out joints. I have a piece of u-channel that I stick underneath to support the cross of the joint or the ears on other sides. Then I stick a big socket on top of the upper cap and press on that. The result is forcing the cross and the upper cap upwards into the socket. Flip over and repeat to get the other cap out

The risk of the "traditional" method is having the upper cap bind up and instead of both caps moving downward, the bottom one moves and the upper ear bends inward.

[lawsoncl]

Scroll to about 46 minutes to see the flipped over version of what I do. He uses a tool on top that presses downward on the cross instead of the upper cap. https://www.youtube.com/watch?v=U6QKs9JajQ4&t=2780s