I'm changing my front end and transfer case fluid tomorrow. So what weight of fluid does the front axle and transfer case use? Any suggestions on very good fluid to use in my 2001 Cherokee?

 

75w95 gear oil for the front diff, and I have no idea of the transfers case

 

75-90 Gear oil for the differentials and Dex/Merc III for the AW4 and T-case.

Any name brand is fine. Avoid the store brands IMO.

 

The NP231 t-case takes Dexron ATF, I suppose you could go synthetic.

 

The transfer case is really not that picky, but as I change that fluid only every 30k and it doesn't take that much to fill it, I use Amsoil synthetic transmission fluid in mine, which is what I use in my AW4. Keeps it simple to use only one fluid for both.

 

and

 

I learned the hard way with synthetic gear lubes in transfer cases and transmissions.
I used it in my jeep and also my muscle car manual trans.....both leaked profusely out of every seal imaginable.

I personally will never use synthetics again although some may have had good results but not me.

I had to buy a new seal kit and reseal my rebuilt transmission all over again two months after using synthetic gear lube on my muscle car.
Nothing like gear lube spatter blowing back onto your exhaust.

Not to mention not good dripping on the drag strip either.