rjlaraway

95 5-speed, 4.0 I6 2door, pretty confident it's the AX-15 transmission but feel free to correct me.

I've put about 4K miles on her since I bought her, currently at 88K miles.

I've seen a lot of older threads addressing this issue but nothing really recently and I'm not sure if the advice is still the same.

Looking to do a drain and fill of the Transmission Fluid and Transfer Case fluid. What lubricants should I be using? 10W-30, Redline, GL-3? And can I use the same fluid for both purposes?

Thanks.

XJwonders

The t case uses DM III fluid but u can easily use ATF 4 for it.

salad

The entire reason people on Jeep Forum started running 10w30 is that Chrysler stopped carrying the correct lubricant when an obsolete transmission was no longer under warranty. They issued a TSB to dealers specifying the change in inventory.

The Aisin-Warner (not Chrysler!) AX-15 was designed for gear oil and should be run on gear oil. The world has moved on from GL-3 to GL-4. GL-5 is kind of like DOT-5 brake fluid - don't use it! It's specially designed for differentials and has additives corrosive to our transmissions. Good stuff now carries names like "synchromesh" as our old brass-synchro transmissions are about the only thing left that needs GL-3/4. Pennzoil and Castrol have products in this category. Myself and others here use Redline MT-90. Best stuff I've ever used in my transmission. Excellent shifting in all weather, and I found it at my local NAPA! Royal Purple has a similar product. You can also use API GL-5 oils that are advertised specifically as yellow metal-safe. (Few, but they're out there).

Transfer case is much less picky. It needs a thin lubricant - so no gear oil! New Process Gear certified the NP231/242 for every major ATF standard out there so just grab whatever red juice you fancy and go with it. A synthetic can be of benefit here as the transfer case has no cooler. It gets quite hot due to proximity to the exhaust.

rjlaraway

Thanks, I'll def be doing the MT-90 for the trans then, it's shifting rough now so hopefully that's a remedy.

zeecherokeeman

My manual says use Dextron 3 for Transfer so yes Salad is right.I have 96 5 speed 2 Door.

rjlaraway

Nice, thanks for all the help. About to order the stuff online I'm going with

3 quarts of Red Line (50304) MT-90 75W-90 GL-4 Manual Transmission and Transaxle Lubricant
2 quarts of Mobil 103529 Dexron-VI Automatic Transmission Fluid

..and a nifty little screw on pumper

That sound about right?

salad

Hmm didn't even know there was a Dex VI. If it's backwards compatible with Dex III and IV go for it. No need to spend big on that item.

The AX-15 takes about 3.5 quarts, so you'll want 4 bottles.

What's a "screw-on pumper"? You need to be able to pump into both the transmission and the transfer case.

If you're feeling rich and hate allen keys (internal hex), check out CCKen's post here about replacing the drain and fill plugs on the transfer case: https://www.cherokeeforum.com/f2/im-...9/#post1669055

rjlaraway

salad

Ohhh okay. Screws on the lid! Duh, of course!

SteveMongr

The Dexron VI is full synthetic and "approved for 2006 and later GM and Isuzu vehicles".
Compatible with Dexron-II and III.
My 2007 Chevy specifies Dexron-VI for the auto tranny(and has no drain plug). It's pricy.

rjlaraway

Hit a pot hole last night and gears started grinding real bad. Left it at the mechanic over night and he just called...said there are some broken gears in the transfer case and quoted me $950 for a JY install and labor. Good news is he'll do the transfer case fluid swap for me so that's one less thing to worry about...

SteveMongr

Wow, never heard that one regarding a transfer case.
They are not difficult to replace yourself, with a JY one costing $100 or so. Maybe get one from anther Jeep person, condition would be better known.
That quote is too high. I work slow and methodical, swapping a transfer case in the XJ would take less than 3 hours (I'm not a mechanic).

rjlaraway

Been calling around to local JY but I guess the NP231 for my I6 Manual isn't readily available , seeing some available online for about the same price $550-700. Mechanic says this is a rebuilt case with a 12 month warranty. Don't have the time to keep hunting for a cheaper one as this is my DD, guess I'm biting the bullet.

SteveMongr

Rebuilt/Re-manufactured is a different story. They do cost $500-$600 and usually have new bearings, seals, and chain or upgraded wider chain. And warranty as you mentioned.
If you need another source for fully reman tranny or transfer case try this company; http://www.manual-transmission.com/

salad

NP231s are NP231s. You can use any NP231 from any XJ provided that you swap the input gear. It's a very simple box and can be rebuilt with a handful of specialized tools, in addition to standard (like $40 outlay). You should be able to pick up a used NP231 - possibly one that was even behind an AX-15 - for $200 or less. Check the local for sale ads here. Your mechanic's quote is WAY too high for a JY unit.

That said I've also never heard of hitting a pothole breaking gears in a transfer case... or really anybody breaking gears in an NP231...