Doug, to make sure you understand, the seal is made of cork or cork-like material. The attached picture shows the seal and collar being moved into place for tightening. The area were the man's left hand is the tube. It moves in and out (axial movement) as the rear axle moves (acceleration, braking etc.). His right hand is on the ball. The ball and it's neighbor parts are made to pivot (angular movement) as the rear axle moves (taking a curve, hitting a pot hole etc.).
Thick cork was/is used to keep the lubricant from flowing out yet allow movement. Cork is porous and a little of the lubricant will leak through. Infrequent dripping is good. As cork ages it become brittle. It can crumble.
Just for safety. The torque tube can be under tension of weight and the energy in the rear axle leaf springs. If you try to remove the U-joint, the tube can crack your head. Always support the torque tube.
I for one would like to hear your results with the square gasket material.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
