[gmack221]

never a bad idea to change the trans fluid, but according to tremec (the maker of the trans) they are lube for life, which means you don't need to change the trans fluid. I just got done doing a rebuild on mine ... but that was because of the previous owners non-shifting ability. The weak link in these tranny's is 3-4 syncro's, & the 3-4 shift fork. If it grinds going into any gear you probably have a bad syncro, if it pops out of gear you have a bad shift fork.