my transfer case on my 99 gmc jimmy is leaking. it is leaking out of the rear seal where the slip yoke enter the transfer case. it started after i replaced the transfer case fluid. i used the blue fluid chevy says to use . i also replaced the seal that the slip yoke goes into. ive tried everything. my next thought is to get a remanufactured drive shaft cause a new slip yoke can only be bought from chevy and cost about the same price as a whole d shaft?my father is a gm service director and told me the slip yokes are known to get groves in them and cause a leak. another thing i was thinking could i be overfilling it. i fill it to the top of the fill plug . i had some say maybe you are over filling it and it is coming out the seal cause it is over filled . i have no idea anymore .. any help would be great . thanks