The Stovebolt Site Forums The Shop Area Driveline Collar on drivetrain 53 truck

Just started working on 53 Chevy pickup. After a month, it is started. Yesterday after driving it I noticed oil dripping out from under it. There is what I'd call a collar which connects the drivetrain to what I believe to be the transmission (I'm learning as I go). That collar became unscrewed. Oil was dripping out of the drivetrain n from behind the engine. Oil pan looks good n valve cover looks tight. Is it possible oil was "slung" out of drivetrain and onto back of engine n that is where oil is coming from? I'd say over 2 days a 1/4 to 1/2 cup of oil has dripped.

Oil form the drive train wil not be thrown forward on to the engine, if that is what you were asking.

Did you overfill the transmission? A picture would help clarify.

The collar you describe is the ball collar where the u-joint is located. There needs to be a pint of gear oil in there to keep the u joint happy.

The oil in the amount you describe is likely a rear main seal. There are many debates on how to perform its installation, but many leak oil.

Which one do you think it is?

I've talked to several people and the main seal is the likely cause they all mention. I had hoped it was an easier fix but I'm afraid it is that. I had a local older mechanic tell me that the drive train gets its oil from the transmission. Is this true? If not how do you add oil to the drive train? Thanks for the help.

or it might be a little of both, wipe it all down and check it after running it and see where its forming at. if its from the ball collar it will be gear oil and if its the rear main seal it will be motor oil. thats how i determined what was leaking on the 40 before i changed to an open drive line and at the time it was both.

" . . . I had a local older mechanic tell me that the drive train gets its oil from the transmission. Is this true? If not how do you add oil to the drive train? . . . "

The entire drive train does not get all of its oil from the transmission. The u-joint/housing and transmission share the same gear oil. The rear end has its own, separate, gear oil.

A bad seal in the transmission end of the torque tube might result in transmission/u-joint oil getting back to the rear end.

The engine oil is lighter weight and completely isolated from the rest of the drive train (except through leaks, as described by 51 ashton.

Have you checked your Shop Manual or your Operators Manual for lubrication information?

If you have a substantial leak that reaches the bottom of the engine, it will drip going down the road and travel back along the bottom ot the vehicle. It usually lands on things hanging down and then drips off them again. If the oil in the transmission happens to be rearend type oil it will appear much thicker than motor oil. Sometimes these clues can help one uinderstand what is coming from where.