What fluid weight are you guys running in your diffs? I was thinking 80-90 with limited slip additive but the guy at autozone said the computer called for 75-140. Is that right? what would be a good weight for my diffs and transfer case?

I have 99 xj 3in lift 31x10.5x15 custom bumpers rack exhuast pretty much a little better than stock, DD that goes offroading one weekend out of the month.

 

Apparently, you can use either weight in your diffs.
Your t-case takes Mopar Dexron III (II no longer exists) or ATF plus 3 automatic transmission fluid though.

 

Recommend Axle Differential for Cherokee.

SAE 75W-90 (API-GL5) For trailer towing applications SAE 75W-140 Synthetic Gear Lubricant in rear axle. Models equipped with Trac-Lok require an additive.

 

Transfer case calls for DexronIII or Mercon.

 

Little tip: If you're going to be sinking the differential don't bother with synthetic, you should always change the oil after it goes for a swim

NP231J is specced for Dexron II, Dexron III, and Mercon in the YJ, XJ, MJ, and early TJ families of manuals. The same transfer case lives on in the TJs where ATF+4 is specified. However as the AW4 transmission is D/M only it's easier to just use the same fluid in both.

 

thanks for the tips and great responses. Since I am in texas and dont have a lot of water to sink the diffs in i will use the syn 75-140.