I planning changing my tranny fluid a rearend fluid. Anyone have any suggestions, besides just synthetic(sp). How much does each one take?

 

Haven't done mine yet (it is due, however) but I believe the rearend requires a GM additive for the limited differential?

 

I have a quick question. I know that the tranny and differential will always at some time need new fluid. Now for the rear-end and rear axle..is that part of the differential or othose different parts that need fluid as well..those two I get confuse on.