have a feeling i might be replacing the Trans
 

well for a while now when taking off i get this thud/bump like the trans is slipping and also when slowing down almost to a stop it does the same thing..i know it is not the u-joints because those were replaced about 15k miles ago..do you think my trans is slipping or t-case? i hope it isnt the transmission...also when i put it in reverse and hit the gas it snatches into reverese like it slips and slams into gear but when driving it shifts smoth if im easy on it

first remove the driveshaft, mark the two halves, infront and behind the slip shaft and take it apart, clean all the grease out and pack it back full, install it in the same spot and try again

i never thought about that..ive never put grease in there and there isnt much in there..i will give that a try..but you think thats maybe the issues im having? my driveshaft is the one with the small piece that is about 8 or 9 inches long then the rest of the shaft slips in into that.

yes....try that

will do i got to replace leaf springs tomorrow so i will definitely give that a try...what kind of grease goes in there?

i just use wheel bearing grease

my truck does the same thing when going into reverse.

packed it full of grease and bam all those issues are gone thanks man i was thinking the tranny was slipping..