[Jack21]

Driveshaft universals are typically permanently lubricated, and need no lube. Some that do, have a grease fitting in it, so use the same grease you use on ball joints. Preferably a grease with a moly additive.

The inside of the shaft with the splines that go into the trans gets the same moly chassis lube. The outside that goes against the seal gets a coating of trans fluid. Make sure this area is squeaky clean, and scratch free. Wipe a little trans fluid on the seal also before sliding the shaft in.