• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

np242 fluid change

Tacedaddy

NAXJA Forum User
OK i just changed the fluid in my 1990 Cherokee 4.0 auto with an NP242 transfer case.
all the reading i've done says its supposed to hold 3 quarts. 1/2 a quart came out :doh: but then only 1.5 quarts would go back in before overflowing. Im parked on a flat surface so idk whats up.

how much fluid have you guys gotten to go in?
 
you have 2 wholes the drain hole (bottom) and the fill (top) just fill the t-case until the fluid comes out of the top whole then close it up. donzo
 
it was brown.. very brown...
still working properly, and man SOOO much better driving down interstate after the fluid change

Im going to pull it apart and check out the internals next week.. im gonna kill the PO, i should have changed it sooner but apparently it was "just changed last year" :rolleyes:
 
Are you sure it was transmission fluid that came out, and not oil/gear lube?

They could have just changed it last year, and put in something like that. Not uncommon as other vehicles in the past have used gear oil in the transfercase.
 
that would be a logical explanation... it also smelled really burnt

but yeh its got ATF in it now, the funny thing is my 4wd has worked great since i bought it.. i was just doing routine fluid changes and got to the transfer case last... of course
 
Slightly off topic, if I bust my tcase will the oil from the auto gearbag be ok? I'm worried about cross contamination into my auto after blowing up my tcase, I'm yet to change out the tcase with one I have to replace it with.
 
Mine smelt like burned sulfur and looked like black molasses when I changed the 87 np242 fluid. I considered getting it carbon dated, :shiver:, LOL!
 
If your output shaft seal on the trans is bad and the TC input seal not perfect either, you can get fluid leaking past the trans seal and ending up in the NP242, raising the level much higher than the fill hole.

Not sure about the color of your fluid being brown, but it could just be old, tired and ready to be changed out.
 
Im going to pull it apart and check out the internals next week.. im gonna kill the PO, i should have changed it sooner but apparently it was "just changed last year" :rolleyes:

I would consider getting ALL fresh fluids in there. If the PO didn't change one fluid, he probably didn't change the others. And changing them now establishes a "baseline" for future maintenance. Coolant (and stat), both diffs, transmission and of course oil and filter.

Fluids are the lifeblood of your vehicle. Always money well spent.

Throw all fresh tuneup hardware in there now as well. Often ignored until symptomatic.
 
When I changed the fluid in my T-case (NP231) it was brown as well. Judging by the other fluids and how the PO of mine knew nothing about maintenance, it was probably original. Same thing though, only took about 1 quart. Where did you read it takes 3 qt? The NP242 on my previous XJ took slightly more, maybe 1.5 qt.
 
I would consider getting ALL fresh fluids in there. If the PO didn't change one fluid, he probably didn't change the others. And changing them now establishes a "baseline" for future maintenance. Coolant (and stat), both diffs, transmission and of course oil and filter.

Fluids are the lifeblood of your vehicle. Always money well spent.

Throw all fresh tuneup hardware in there now as well. Often ignored until symptomatic.

As stated the tcase was the last thing i changed... all other fluids have been changed. Every companant on my engine is new. distributor cap, button rotor, alternator, belt, all hoses, radiator, spark plugs, oil, filter, motor mounts, intake manifold gasket, valve cover gasket, head gasket, valve seals, lifters, ECT... i did an entire rebuild on my 260K motor

im a very competent mechanic just wanted to know what the proper amount of fluid in the NP242 case there bud

the 3quart might be for a complete teeardown
that thought literally just crossed my mind. thanks man
 
Ya, also curious as to where you saw 3 quarts for the 242? I never saw that for mine in the manual or FSM.

Also does not explain for a complete tear down, the t-case does not retain fluid anywhere (in large amounts, small little puddles may still exist), like an automatic transmission does. Tearing it apart and putting it back together still uses ~1.5 quarts. And the fill procedure is always fill it until it starts leaking out the fill plug.
 
I bought a used 242 from a rolled 1999 XJ. It had around 109,000 miles on it. The first thing I did was check the oil. About 1.5 pints came out and it was brown, and the consistancy of molasses. I figured I'd been had but when I pulled it down to inspect it, it was like new inside. Put it back together with new seals and installed it. Other than a leaky speedo adaptor and rear output seal it runs like a champ. Drained the oil after about 100 miles and the fluid looked a little brownish, which is understandable. Fixed the leaks so I'm all set. I will change the oil again in about 500 miles to make sure all the crap is out of it.

The one that came out my 99.5 XJ, the cover is cast marked 99 and 00. The one that came from the donor 99 is cast marked 98 and 99. The 98/99 TC has a placard that states 2.85 pts and the 99/00 TC is pacarded 3.0 pts. Why there would be a difference in capacity I don't know - nor does it really matter. Just thought I would mention it.

Was using ATF+4 in the old TC, and then to Valvoline DEX/MERC, but for the replacement TC, I've switched to Advance Auto Parts DEXIII/M fluid....much cheaper than ATF+4 or DEX/MERC and does the same job as the big buck fluids. When I think about it, I think these NPG/NVG transfer cases could run on vomit without hurting them.

The reason I changed my TC was that it was making noise and there was lots of metal (bronze) in the fluid. Teardown shows that the bronze ring on the Differential Sprocket (P/N 83503536) had two pieces of steel chunks impedded in it and was chewing up its mating/rubbing surface inside the differential as well as the bronze ring. The steel chunks came from the leading edge teeth of the Mode Synchronizer Sleeve (P/N 83503542) being broken off when 4WD FT was engaged over the years. The Differential is trash. The differential half chewed up by the bronze ring is non-procurable by itself. New differentials are outlandish - $550.00 is the cheapest I could find. Used differentials probably have chewed up bronze rings/differentials as well. I'll sit on this for awhile I guess.
 
Back
Top