My transnission man tells me to run mobile 1 5w30 in my AX15 and t-case so that is what I run

 

Is this the same guy that will be rebuilding both. :rofl: Seriously, 5w30 is fine for both. I run 75W90 full syn in my AX15 but full syn 5W30 is fine also. I use ATF in my transfer case. It's just preference.

 

What is suppose to be better in synchromesh?

I just did my tsace this year with atf, havent had a problem yet.

 

ATF, Synchromesh, whatever floats your boat. There seems to be a lot of hatred towards Pennzoil though.

If you ask me, throw ATF in it.

 

The only thing I am hesitant about is putting synchromesh in the tcase. It might be too thick for the tcase oil pump to pick up and move properly. I guess there really aint nothing in there that needs it anyhow. I'll go with a good synthetic ATF.

I'm going to try it in my AX-5, however. If it doesnt make a difference in shifting then I will try Mobil 1 on the next go around.

There's so many differences of opinions and experiences out there that I would rather trust my YJ peeps here than anyone else. unk:

 

I just changed all my fluids and used ATF. Remember ATF is high detergent... I don't know about the Mobil 1. I imagine it is somewhat detergent, but I don't know the specifics on it.

 

Well we all are going to have our opinions, however I decided to go with the advice from the man I have trusted for over 20 years on what type of fluid to run. He has been telling me to run the Mobile 1 in standard shift transmissions for years. Now there are some transmissions out there that do use gear lube, but the later model, aluminum case type of transmissions he recommends Mobile 1.

 

I pulled my tcase today to install an SYE, and while I'm there I drained my tranny for a quick fluid change... Sumbitch, gear oil came out. This is from the PO and I really hope they used a GL3 or GL4 oil and not GL5. I didn't see any brass in the drain pan, so hoping for the best. :facepalm:

I got some ATF 4+ for the tcase today, and Pennzoil Synchromesh for the tranny.

 

I use Royal Purple Gear oil in my BA-10 and Royal purple ATF in my T Case. I was having shifting problems with my Trans, just wasn't very smooth, when I drained it and put the RP back in, she smoothed right out. Love that stuff.

 

I plan on using Mobil 1 Synthetic 10w-30 when I fill mine up tomorrow, thats what I seem to hear/read everywhere I turn.

 

Synchromesh in my AX5, ATF+4 in my NP231, Seriously, if you run motor oil or Synchromesh in your Tcase you will burn out your pump.

 

Synchromesh in my AX5, ATF+4 in my NP231, Seriously, if you run motor oil or Synchromesh in your Tcase you will burn out your pump.

No you wont. Ran Mobile 1 in my transfer case for over 2 years with no problems. Took the t-case to my tranny shop for him to check it out and replace anything that needed to be replaced. Everything inside was just fine including the pump.

 

Oil is oil. Something is better than nothing... So many opinions on this subject it's stupid. Here is mine. It's your jeep do what ya want. You will never get a solid answer on this topic on an Internet forum.

 

AMEN!!!!!!!!!!!!! :thumb:

 

whats the difference between ATF and ATF+4?

 

ATF covers all types of the hydraulic fluids that fall in the category, When our Jeeps were new they used Dexron ATF. Currently all Chrysler products use ATF+4, which is a full synthetic type of ATF

ATF = Automatic Transmission Fluid
Dexron, Type F and +4 are all different blends or additives, with the +4 a synthetic blend.
There are other blends, I only listed the majority of what you will most likely hear on the forums.