The Stovebolt Site Forums The Shop Area Driveline replacing seals - can do it? (universal joints)

One or 2 of these universal joints are leaking oil so hopefully I can replace the seals myself. What specifically do I replace & where do I order them?
Thank you!

What piece do you want to replace?

The red is a carrier bearing, the yellow is the u-joint.

Both are replaceable, but neither one has any oil in them. That looks like oil blowback from the engine side.

In addition to the "oil", it also looks like that "grease" is slung from the u-joint. Often happens if the joint is greased with a grease gun to the point that grease escapes around the needle bearings/cup/seal. Unless there is "movement / play" in the carrier bearing or the u joint, clean it up and keep driving it.

I just want to stop the oil leaking from it. Does the oil not come from the transmission? I topped it up after changing it. Wouldn’t it need new seals?

That leakage and grunge is most likely slingage from 70 years of use. After a proper cleaning and servicing you may be pleased with how little it continues to sling off. Clean it up and check it out for play... "If it ain't broke, don't fix it."
Matter of fact... I like to see that... tells me the OP didn't mind pumping a grease gun.

Unless the front portion of the driveshaft is enclosed (and it doesn't look like it in the photo), then there's very little chance of oil from the transmission getting back as far as the carrier bearing. Post a photo of the rear of the transmission (and the u-joint there), and we'd be able to tell if there's a leak there. But the front shaft doesn't look very oily, which would indicate oil running down it to the are of the carrier bearing. Grease has some oil in it that's left behind after the more solid stuff is flung off.

The shaft is enclosed, oil drips off from the bearing flange. Leaving a pool of oil on the cement. I do see where grease has slung off the u Joint for a long time.

There is a seal between the driveshaft tube and the shaft itself in the vicinity of the carrier bearing. It's show in Figure 79 in the 48-51 Truck Shop Manual (attached). You'll have to remove the front shaft to replace that, and you might as well replace the bearing inside as well, although it has been well lubricated.

Thank you sir. Sorry to respond late but I’ve been out of town.

Back with you! Been busy fixing other items and saving this for now. The torque tube is positioned at the rear transmission to the Bearing flange midway back. This is the place I see oil dripping onto the cement floor. It has slacked off on that leaking ( I have been driving it trying to seat the rings in the new motor) so I plan to check the transmission fluid level to verify it is leaking as will as it's not gotten too low. I went ahead and ordered a drive shaft tube seal thinking it is bad. This is a 1953, 3/4 ton truck so it looks to me that the parts are different than earlier ones. Like I don't think it has an Okie bushing seal to deal with? Just looking for verification from my friends here.
Thank you,

I cleaned most of the old grease that flung around. I see a drop if oil in the flange. The transmission oil was plenty full but not running out & it does not flow from the differential. So I can repair it when the part comes in or just keep checking it.

😳😁
I found these gaskets & seal. I think the one in the bag is for the front behind the transmission? The other is the seal needed for maybe just the mid section??
It only leaks so probably does not need anything else replaced.

If that seal fits, that should do the trick. You may not have to disconnect the ball from the rear of the transmission, but if you do, you'll need to determine the number of gaskets needed for the proper tension at the ball. Might be less of an issue with the intermediate shaft than on a 3100 with the torque tube without the intermediate shaft. That needs to be done without the cork gasket in the ball cover. The service manual covers that adjustment and figuring out how many gaskets to use.

If it runs fine, isn't noisy, but only drips slightly, leave it alone. Most of them will still leak some even after you replace the seals and shim the torque ball properly.
In the meantime, keep an eye out for when it quits leaking on the floor. That's your indicator to check the transmission fluid level.

Thank you!