I did a search for this, and I came across an old topic saying to use

Mopar Dextron II, or ATF Plus type 7126 automatic transmission fluid for the transfer case.

Is this correct?

What is the consensus on which is best?

 

Mopar ATF +4 Be had at your local walmart..

 

According to my build sheet, I have the 231HD t-case. If I remember correctly, the fluid cap on that is 2.5 qts, right?

Thx

 

haynes manual says dexron III
dodge ram owners manual says ATF+4.

i just did mine and used the same valvoline ATF+4 that i used in AT. got it at autozone for 4.99/qt. i saw the wal-mart super-tech brand for a lot cheaper, but was scared to use it...

my t-case took 1-1/4 qts to fill.
TIP - the damn fill and drain plugs are recessed 3/8 (or some mysterious metric) hex heads in soft aluminum plugs. REMOVE the fill plug first to see if you have a disaster or not. then remove the drain plug. if you don't have a hex tool you could probably use a bolt turned backwards with some locknuts. TAKE all precautions not to strip out your hex shape. naturally mine was torqued to about 50 pounds. i used some liquid teflon sealer and only tightened to about 5#.

 

I would go royal purple atf.

 

What about Lucas? I have heard many ppl swearby the stuff, but IDK if they make tranny fluid...guess I can run to Autozone and see.

 

I used Dexron III last time I did mine, but read something on PS.com that you should use ATF+4 on trucks with auto trans because if you lose the seal between the trans and the transfer case, the mixing fluids will be the same.

 

Ain't got a trans. case, but I've heard the same thing... ATF +4 in case of the seal going.

 

I am using Royal Purple Syncromax in my T-case (which is a NV231HD from JB Conversions).

I started using RP in the t-cases whenI had my TJ. I changed the fluid out to the RP Syncromax and the T-case quieted down a lot and seemed to shift easier as well. So whenI had to fill up my new JB Conversions case I natuarally went with RP again and so far it's been doing great (5K miles on it now).

I also use it in my NV3500 which is supposed to run the Dodge synthetic for the 5spd only, but RP's rating matched the Dodge crap so I put it in there. I can definetely tell that my 5 spd shifts much smoother than it did with the Mopar Synthetic in it.

When I get around to it in the spring I am going to change out the diffs with RP too!

I used to think "one size fits all" with oil, but I am a firm believer in the RP products now.

 

Dodge calls for ATF 4. No sense screwing around with non-spec products. Before you choose an alternative fluid, consider this question:

Would you use a rear diff fluid that didn't contain an LS fluid in a rear that was limited slip? How about Diesel fuel in a gas engine?

ATF 4 is worth the good night sleep, especially since there are options other than Mopar - you have choices from reputable vendors.