Vehicle is a 1998 Chevy Blazer S10 with 4.3L V6 gas engine.
Transfer case is NV233, and takes either GM Auto Track II or Dexron VI. Front and rear differentials take 80w-90 gear oil.
I would like to drain a little of the existing t-case fluid and add some Trans Tune a week or so before changing the fluid; and am also considering adding some Trans Tune with the new fluid.
I’m also looking for a good way to flush out the front differential (without taking it apart), since the old gear oil in it is very dirty.
Is Trans Tune compatible with the Auto Track II fluid that’s currently in the transfer case? Would it be a good or bad idea to add some to the new fluid (and how much)?
Would Trans Tune work in the front differential? Would Sea Foam Motor Treatment be better? Should I drive it with the additive in it, or just fill and drain?
Great questions, Phil. Trans Tune is compatible with the fluids you’ve noted. Trans Tune will mix evenly and work to reliquefy any heavier fluid residue to help drain more easily when time to change out the fluids. Figure adding 2 ounces for every quart of fluid or gear oil, then operate to circulate for at least one hour before changing. Right after draining the old fluid and lube, can use Sea Foam Spray and straw to reach in and wash the inner areas (if accessible). Just spray around to help draw out the stubborn goop. Hope this helps!