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Quick NP231 Fluid Question

4

4WDlifeform

NAXJA Forum User
Location
Beaver Falls, PA
Hey guys, hate to open a new thread for a few simple questions, but couldn't find this info...

I am doing fluids today, motor oil, NP231, AX-15, and coolant.

I'm most concerned with the t-case. I have mobile 1 synthetic for the AX-15, heard that makes an improvement. can the same oil be used in the transfer case??

Also, how much do I need for t-case?? I'm under the assumption that the same oil can be use for the trans as for the t-case. Please correct me if i got it all wrong! I have 6 quarts of the mobile-1 synth.

Thanks in advance for quick responces!!
 
For a 242 transfer case the fluid might be somewhat important, but for a 231 I'd just use whatever has the right viscosity and lubricates well. I keep cheap ATF around for making penetrating lube and the transfer case though, so that's what I use.
 
Yeah, I got the post, I just dont get why ATF is recommended.

Viscosity Index of Dexron III is 180
Viscosity Index of 10w-30 is 147.

Im going to play it safe, and go with what is suggested. Thanks guys!
 
ATF is REQUIRED for the t/case because it has an itsy-bitsy tiny-weenie pump that can't handle anything else but ATF.

As there are no CLUTCHES in the t/case, it really doesn't matter what type or brand of ATF is used, however Dex III is specified--that has more to do with the AW4 having been specifically built to use Dex III, and it makes sense to use the same fluid.

So, if you put motor oil or gear oil in your t/case, start shopping for a new t/case as you will need it pretty soon.

Any questions?

Ok, this will be on the test.
 
Do a little more reading before adding Mobil1 for the transmission. I recall something about the synchros not liking Mobil1.

The TC takes ATF.
 
kastein said:
For a 242 transfer case the fluid might be somewhat important, but for a 231 I'd just use whatever has the right viscosity and lubricates well. I keep cheap ATF around for making penetrating lube and the transfer case though, so that's what I use.
Click to expand...

I agree, for the 242 I would use the best synthetic ATF available & Change it often, especially if you run in Full time mode.
Only because it seems to run hotter than the 231. Whenever I changed my GC with the 242 TC fluid it was getting dark, Every 231 I ever changed had what looked like brand new ATF come out of it.
 
CaliGold said:
Do a little more reading before adding Mobil1 for the transmission. I recall something about the synchros not liking Mobil1.

The TC takes ATF.
Click to expand...

You got the yellow-metal issue right, but the wrong lubricant.

The AX15 was originally specified for GL-3, however along the way some owner's manuals were printed with GL-5, and that was an error as GL-5 will attack the yellow metal synchros in any transmission where they are used.

You need to use a yellow metal safe lubricant in the AX15. Original GL-3, but good luck finding it. Red Line MTL 90; Pennzoil Synchromesh; the gen-u-wine Chryco $22 dollar per quart new and improved 75-90 synthetic lubricant (Did I mention the $22 dollar a quart price tag?); or a high quality synthetic 10w30 motor oil--Mobil -1 comes to mind.

An extra benefit of the synthetic 10w30 is easier shifting, particularly in cold weather. Users of MTL 90 and Synchromesh also report better shifting.

There are combination GL-3/GL-4/GL-5 products out there--DO NOT USE THEM UNLESS THE CONTAINER STATES YELLOW-METAL SAFE!!!
 
ok! finished 3 out of 4 today... yet to do anti-freeze.

First off, thanks a lot for all of your replies! I went and got a "well priced" ATF for the 231. Thank you joe_peters for the info!! Makes sense now, and glad you guys were here to keep me in the right track. Drained the t-case fluid, and it was BLACK. so, glad I swapped that with ATF.

I went ahead with the synthetic 10w-30 by Mobile-1. I took it for a drive, and I cant say 100% improvement... but certainly felt better on a cold run. So, Im happy with that, and Its not going to eat the bronze. I went with that, as there was alot of positive feedback running that in the AX-15, and it was locally available.

Motor oil came out BLACK as well, due to the sea-foam treatment that was in it for the last 300 miles. Replaced with traditional 10w-30, with a quart of MMO in place of a quart of the reg oil.

Woooo. what a messy day today was haha.
 
Job well done--time for a steak and your favorite beverage!
 
4WDlifeform said:
ok! finished 3 out of 4 today... yet to do anti-freeze.

First off, thanks a lot for all of your replies! I went and got a "well priced" ATF for the 231. Thank you joe_peters for the info!! Makes sense now, and glad you guys were here to keep me in the right track. Drained the t-case fluid, and it was BLACK. so, glad I swapped that with ATF.

I went ahead with the synthetic 10w-30 by Mobile-1. I took it for a drive, and I cant say 100% improvement... but certainly felt better on a cold run. So, Im happy with that, and Its not going to eat the bronze. I went with that, as there was alot of positive feedback running that in the AX-15, and it was locally available.

Motor oil came out BLACK as well, due to the sea-foam treatment that was in it for the last 300 miles. Replaced with traditional 10w-30, with a quart of MMO in place of a quart of the reg oil.

Woooo. what a messy day today was haha.
Click to expand...

So wait, your running 10w-30 in your trans now? :confused:

Let me know how the seals in your engine are after running sea-foam through the motor oil at 120k+ miles
 
xjchris98 said:
So wait, your running 10w-30 in your trans now? :confused:

Let me know how the seals in your engine are after running sea-foam through the motor oil at 120k+ miles
Click to expand...
I know this question was aimed towards him, and yet all engines are not created equal. I have used seafoam, in several different 4.0L's and other engines as well. The 4.0L's that I have used them in are just fine. Most of the 4.0L's I have used seafoam in have had more than 100+k on them. Most of them did not have much smoke come out afterwards as well.
 
xjchris98, he's got a manual transmission. I don't think an aw-4 would like 10W30 very much though :shocked:
 
Johnnie Walker said:
I know this question was aimed towards him, and yet all engines are not created equal. I have used seafoam, in several different 4.0L's and other engines as well. The 4.0L's that I have used them in are just fine. Most of the 4.0L's I have used seafoam in have had more than 100+k on them. Most of them did not have much smoke come out afterwards as well.
Click to expand...

Seafoam works well, but i've always been told not to mix it with your oil if your motor has alot of miles on it. Its just personal opinion....but I dont see the benefits of running it through the motor over risking creating an oil leak somewhere because it ate through one of the seals.

kastein said:
xjchris98, he's got a manual transmission. I don't think an aw-4 would like 10W30 very much though :shocked:
Click to expand...

I know he has a manual....I know the kid personally. Im just saying i've never heard of someone putting 10w-30 in a transmission (auto or manual)
 
No oil leaks... yet... Never hurt the explorer either haha. Engine is actually running more quiet and smooth sounding... not by much, but at idle, I noticed a difference.

and, transmission is working great! smoother shifting noted.
 
I've been running the Mobil1 10w30 in my ax15 for a few months...to be honest, didn't like it at first, but now it's all good and shifts smoothly.
 
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