gear oil... what should I be useing?

For motor oil I just use whatevers cheap and change it often... most my conserns are about the other parts. All of this is on a 1995 Cherokee Sport. Also if someone has seen a DIY for changeing these fluids, please point me in the right direction.

Transmission (5-speed): I have no idea?
transfer case: same as transmission?

Front and rear diffs: 75w-90 syn or not?

I'm new to jeeps, any help is greatly appreciated.

skidder1 said:

For motor oil I just use whatevers cheap and change it often... most my conserns are about the other parts. All of this is on a 1995 Cherokee Sport. Also if someone has seen a DIY for changeing these fluids, please point me in the right direction.

Transmission (5-speed): I have no idea?
gear oil GL-5 I think, no need for syn unless you want it

transfer case: same as transmission?

no, atf +3 i think is the spec, thought it might be dex/merc

Front and rear diffs: 75w-90 syn or not?
no need for syn, but it is up to you GL-5 is fine


I'm new to jeeps, any help is greatly appreciated.

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glad to help

Thanks

For the tranny, AX-15, you will want to run a GL3 or GL4 because it has bronze syncro's. The sulfur in the GL5 oils will attack the bronze makeing it harder to shift and wearing your parts out too fast. All the FSM's say to use GL5 but if you try to buy some from a jeep dealership they will sell you an engine oil (may have been a straight 30 weight but I can't remember.) I went for the Redline MT-90 and it shifts much smoother. Just about any ATF should work, I use ATF +mercron. My axle's are just getting the cheap NAPA stuff.

~Alex

You might need an oil with the friction modifier if you have a limited slip in the rear. x2 on the mt-90 for the ax15 and redline has a good 75w-90 w/ or w/o the ls additive.

gradon said:

You might need an oil with the friction modifier if you have a limited slip in the rear. x2 on the mt-90 for the ax15 and redline has a good 75w-90 w/ or w/o the ls additive.

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unless you use synthetic, which doesn't require it.

X3 for the Redline MT-90.

GL-4 also has the sulfur in it that can hurt your Bronze/Brass Synchros. The fluid has to get to a certain temperature to make the additives in GL-4 and GL-5 type trans fluid/gear oil to become corrosive and hurt the synchros. Thus, you'll hear testimonials where some say they used GL-5 and never had a problem, and others say they used GL-4 and it destroyed their transmission. I guess it depends on weather you stress your tranny and motor enough to get the fluid hot enough to make it become corrosive to the synchros.

Redline MT-90 is GL-4, but in their literature, they state with the synthetic and additives package they use, the fluid can get twice as hot as regular GL-4 before it becomes corrosive. Something like 450°, which I would think your seals would all melt and the fluid would come pouring out before you reach that temp.

The Redline MT-90 and its lighter sister product MTL, has lots of friction modifier that helps the synchros engage smoothly. Some argue whether its needed are NOT for the Jeep AX 5 speed trans. Some trans don't need it, some do need it and the gears will grind while shifting without it. IMO, it can't hurt to have it in a smaller vehicle where the trans load aren't that great, it makes your shifting smoother and easier.

There was a noticable difference, especially shifting into second when I switched from whatever the last guy put in to the MT-90. The stuff that came out stunk like sulfur and there was so much bronze in it I could almost see myself in its reflection. JK, but there was alot in there. I have done 2 trans fluid swaps and the last stuff came out pretty much clean. I definatly give my tranny some punishment, thats why I use it.