Fluid types

[jeepaholic]

AX-15 and a NP231...What are my best fluid choices..Strictly offroad vehicle..need to know for both.

[Pete M]

The 231 gets ATF. The AX-15 gets 10w-30 engine oil (Chrysler changed it from the old stuff that would eat the synchros). There are other aftermarket choices, but I'll let the others chime in with those since I probably won't get them straight..

[mjeff87]

I'm running Mobil 1 75/90W synthetic in the tranny, but am going to try the 10W30 at the next change (which won't be anytime soon considering how often I drive mine, unless I drown it in a water crossing.....)

 

Me likey the idea of $2.50 per quart of Castrol versus $9-10 for the Mobil :D

 

Jeff

[landlubber]

what about for the BA 10/5?

[Geonovast]

I've noticed the 10W-30 popping up a lot lately with more than just our transmissions, does it require fluid changes more often?

[Wildman]

what about for the BA 10/5?

 

It calls for SAE 75W-90 GL-5 gear lub, 4.9 pints for 4wd and 5.2 pints for 2wd.

 

If your up north, use the synthetic, it will shift easier in the cold weather.

 

This is also the same gear lub for the axles.

[jpdocdave]

I've noticed the 10W-30 popping up a lot lately with more than just our transmissions, does it require fluid changes more often?

 

i didn't know its been coming up, i'm kinda interested. i've heard of it before. i did put 50w in my ax5 in an old yj that started to shift harder, actually did improve with the thinner oil. i've heard of atf in manuals to, not sure if i'd do it or not.

[landlubber]

ah, I put 90w out back. thx for the info.

 

gotta change the tranny fluid too, only see a drain plug all the times i've looked.

[Pete M]

The big reason they changed the fluid required in the AX-15 is that the old fluid would eat the yellow metals (aka the synchros) inside the transmission (other transmission don't have this issue). Chrysler certainly won't acknowledge that and so they say it's for "improved shifting".