REL1203

Is it acceptable to use 75W-140 Royal Purple Gear oil in a JK? I am about to put on my Solid Diff covers and do my first Diff Oil change, and i have 4qt of 75w-140 RP Gear Oil... Is this ok to use, or does it have to 75w-90?

randyd

I would use exactly the weight of lube required by Jeep. Why second guess them.

mkjeep

I run the 75-140 RP in mine, changed to it at 15,000, I'm at 31,000 now. Holding off for a couple weeks till I change my gears before changing again. No probs.

Eugene

Running the same in both front and back. So far so good.

REL1203

so some run 140, some run 90... What am I to do....Is there any issue with running the 140, i honestly dont know what that number corresponds to really

odin725

I am pretty sure that Jeep says run the 75w90 but it also says if you tow a lot to use the 75w-140 so my guess is it would be fine either way.

REL1203

If I am never planning on Towing, but do Offroad (obviously), is there any benifit going with the 140?

Bronco_Bustin

Depending on what kinda wheelin you do.... you could create strains much greater than if you were simply towing on the road. Such as spinning oversize tires at extreme articulation angles. The pros: a little extra protection in extreme conditions. Cons: Possibly, depending on how cold, a little extra drag, at least till it warms up. Does it really matter either way? NO.
Good Luck
Eeny, meeny, miny, moe!

kurtfriedrich

Think there is any chance Jeep would refuse warranty work if you use Royal Purple Gear instead of their mopar stuff?

Anyone know how many ounces a D30 takes? (stock 08 JK front)

thanks

mkjeep

The owners manual says use mopar OR equivalant. RP or any other gear oil would fit into that category as long as it was SAE 80w-90 or SAE75w-140. If it's stock d-30 with no aftermarket cover, it'll take a little over a quart. 1.3 I think. Fill it till it runs out of the fill hole and your good.