The grease is on the drive shaft for initial start up--before the tranny fluid can get back there to lube the seal. After you drive for a bit, the tranny fluid will do all the lubrication the seal needs.
(I assume you are referring to the output seal when you say "rubber bushing.")
David,
Thanks for the info as I have ordered a driveshaft the other day and that was a question that I had. I guess you answered my question. Also,
guys thank you for such a prompt response.
David- Could you please tell me the location of the 4" hole in the trans tunnel for my TKO 600? I would like to measure up and over from the rear driver's side corner.