Fluids do not leak "uphill". Clean the front of the tube with the ball pivot ahead of the gland nut thoroughly, and inspect it carefully for a pinhole or a crack in the weld. Lube from the back of the transmission will be surrounding the U joint, all the way back to the seal in the Okie bushing a few inches behind that gland nut.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!