The Stovebolt Site Forums The Shop Area Driveline Torque Tube Slip Ring

I'm new, but I have done a lot of reading. I have a 48' 1/2 ton. I had a leak at the slip ring. I pulled the old gasket out of the slip ring and found I have both steel rings and the gasket was in good shape. Got everything back together and compressed. Where I'm stumped is how to refill the oil that leaked out. One place said unscrew the square plug on top. The next said don't, but unscrew the speedo and fill there. It appears to low and small to do any good. I have already changed the 4 speed manual tranny oil. Please help. I afraid to drive because I don't want to screw up the universal joint.

If you haven't disassembled the ball and U-joint then it
should still have enough lubricant to get started with. It's
not like a pressure system, just simply a splash type bearing.
Make sure your oil level stays just below the fill hole on the
side when it is cold. After you drive it a short distance
lubricant will work its way back to the U-joint. Check the
fluid level several times after a refill till things level
out.
If you've disassembled and cleaned/serviced the ball and U-joint
and it is dry, then GM instructs you to add lubricant at the
top of the tail housing thru the VERY SMALL 1/8 NPT hole seen
with a pipe plug in it here in this picture.
http://www.pbase.com/dennygraham/image/141699781/original
Be aware that if you add oil at this point, that is is going
to add to the level in the transmission. You don't want the
oil level to get over the fill hole when the oil is hot or it
will puke out the front of the transmission.
dg

I have not disassembled the ball joint. But just so I'm clear. If I add oil through the side of the transmission fill plug, then it will flow all the way through to the ball joint, right? So, you are saying if I just keep topping off the side fill plug, I will be OK, right?

DG... using your photo, can you mark which hole I should use to refill the ball/universal housing? THX!!

Yes
Yes

fill plug

You do not want to fill it to the top.
It is better to fill the transmission. Then, check it, and if necessary, top it up again.

Not so Tim. The transmission "fill plug" and where you measure
the fluid level is where the two red lines cross in that picture
I posted. Even with the bottom of the hole when hot, hang your
pinkie in the hole at the first knuckle when cold.
Yes, the lubricant will work it's way back into the U-joint/ball
thru the rear bearing when you drive it because the gears pick
it up and splash it all round the inside.
dg

1949 - 1953 Passenger Car Shop Manual w/1954 Supplement
Assembly Number 5.
Remove speedo gear and fill ball housing with 1/2 pint gear lube.

I thought it depends on what transmission you have.
3 speeders don't have that pipe plug.

Car & truck use the same size ball housing.
Pipe plug or speedo gear, 1/2 pint of gear lube will suffice.

Well, this is what I'm talking about. One place says one thing and another says another. DG, yours does make the most sense. I will check the levels as you described. Thx.

Denny,

I thought the question was about the fill plug near the u-joint (used by the factory?). Not being sure, I pointed to what I thought was being referred-to.

And, that is why I made separate reference about the transmission fill plug being the better option (as per the Shop Manuals).

Right, I understand, and you could even fill the trans from
that 11/32" hole back there. It might take an afternoon and
you would have to monitor the side 'fill' plug closely, but it
is possible. But I doubt the factory filled the transmissions
at the point. And I suppose you could fill the trans by
removing the speedometer gear also but.....isn't that why they
put a 'fill' plug in the side of the transmission????
The 1/8" NPT pug at the top of the tail housing of the four
speed, I believe, was meant mainly for when the U-joint was
serviced and to avoid starting the truck with the bell dry.

Again, if it's been previously lubricated then there's really
no need to fill the cavity, other than to more quickly even
out the fluid level, which is just as easily accomplished by
checking the 'fill' plug a couple of times, after driving the truck.

This simple task of checking and adding fluid to the
transmission is turning into a cluster #$%& of major
misunderstanding so do as you will, I'll do as I will!

dg