slip yoke has a groove in it.

[joe1982]

so i was taking advantage of some free time today and getting around to some things that need fixin on the old truck, u joints. i did the rear, when i finished the front where the drive shaft goes connects to the yoke, i noticed that it had a good sized groove in it. can any one tell me what would cause this? would a bad untreated u joint do this, or is it another much larger problem? the yoke also had some shavings inside, not a crazy amount though, just a little. thank you in advance!


joe.

[westofb]

The grooves are just normal wear where the seal in the rear of the trans makes contact with it. As long as it doesn't leak I would not worry about it, if it starts leaking, the only fix I know of would be to replace the yoke. Harmonic balancers get those grooves as well where the seal on the timing cover rides on it, they do make a sleeve for the balancer though to keep from having to replace it.

[James McClure]

The marks you see are from the sleve bearing in the tail stock of the trans. The 2 marks about 1/4" appart are from the seal. IF the marks closest to the begining of the yoke do not appear even all the way around, the yoke is whipping inside the bearing because the "U" joint is tight in one plane. The groove you see inside the yoke is put there on purpose at the factory to allow fluid to move in and out of the yoke. Without that "slot" the yoke will not slide in and out of the trans easily when your loaded\empty or going over bumps. Get enough oil in there and hit a good sized roll in the roda and the pressure will punch the welch plug in the back of the yoke right out and cause some leakage. Sleeve bearing is easy to do, not much more work than doing the seal. Remove tail housing, knock old sleeve out and knock new one in to the same depth. Fit to yoke before putting the housing back on. It will be tight. Use a little very fine lapping compound to get it to move easily. Clean bearing and yoke and reassemble. Jim