The Stovebolt Site Forums The Shop Area Engine Shop u joint lubrication

I'm sure that this has been addressed here many times but I couldn't find anything with a search. I hooked up my drive line this weekend on a 49 1/2 ton. The manual says "remove the special square headed plug and lubricate the u joint". My question is what do you lube it with, how much, etc. The manual tells you to add 1.5 pints of 90 weight to the tranny but nothing about what to lube the ujoint with. Any help?

I assume we are talking about an enclosed driveline.
Doesn't the oil in the tranny also lubricate the u-joint?

Yes, enclosed drive line. The manual says to lube the ujoint through the Square head plugged hole. But no specifics.

Hmmmm, Is this the square plug on the side of the tranny where you put it's oil into ?

There are two plugs on my three speed. One is on the side in the area where the actual gears are. The other is further back just ahead of the ujoint. It is an indexing pin I think but the manual refers to lubing the ujoint thro this hole.On the VCCA forum someone said to put about 1/2 pint of 90 weight in this hole. Have not been able to confirm this from anyone else

The U-joint is lubricated from the transmission. Some of the transmission oil ends up in the "bell" behind the tranny which surrounds the u-joint. That oil remains in the ball to libricate the u-joint and is stopped from running down the torque tube to rear end by an "okie bushing" or the factor equivalent of same. There are two square head pipe plugs on the transmission, the one at the top for adding lubricant and the one at the bottom for draining the transmission. The top plug is the one your manual refers to.

I should correct myself. There are three square head plug on my tranny. The two you refer to which I understand are for filling and draining the transmission fluid. However the shop manual refers to removing the "special square head plug and lubricating the ujoint" That is what my original question was about. This plug is just forward of the ujoint and higher up on the tranny case than the tranny filler plug. It is also smaller in diameter.

Yeah RWise, that's the little 1/8" plug on top by the u-joint. I just sqirted a little gear oil in there. Not much,just a squirt. I greased the u-joint good when I assembled it,so I figured it's protected till it gets some lube from the tranny.