You're lucky, get a big jug of 10-30 high mileage oil, I like Castrol or Valvoline. Your engine and transmission take the same Dino juice, the TC will take auto transmission fluid.

 

Make sure that what you put in your trans is "yellow metal safe" to protect your syncros.
I was using synthetic in my engine until I found out on this forum that synthetic will sneak past older seals quicker than dino oil.
What does your manual say to use?
Good Luck, L.M.

 

Can't go by the manual as Chrysler changed their recommendations to standard 10-30 Motor oil for the AX 5 and AX15 tranny. Always use just plain old Dino juice in the tranny, the cheap stuff is fine. I would never use synthetic as a motor oil in these old motors as the rubber seals are "used" to Dino juice.
This is why I said 10/30 high mileage, it's nice to have one oil that will work in both situations.

The yellow metal warning is for gear oil which is no longer suggested for these transmissions, your standard 10-30 motor oil is fine.

 

Can't go by the manual as Chrysler changed their recommendations to standard 10-30 Motor oil for the AX 5 and AX15 tranny. Always use just plain old Dino juice in the tranny, the cheap stuff is fine. I would never use synthetic as a motor oil in these old motors as the rubber seals are "used" to Dino juice.
This is why I said 10/30 high mileage, it's nice to have one oil that will work in both situations.

The yellow metal warning is for gear oil which is no longer suggested for these transmissions, your standard 10-30 motor oil is fine.

I do believe that Aisin "allowed" the use of SYNTHETIC 10W40 motor oil due to the difficulty in finding a GL-4 rated 75W90 gear oil. They allowed synthetic due to its ability to withstand higher shear pressures than standard motor oil. Most manuals are incorrect instating that you can use a GL-5 gear oil, They have a higher sulfur content (to improve shear performance) and that sulfur will pit the sycnhros with copper content (brass/bronze).
I found that I could order Amsoil 75W90 full synthetic with a GL-4 rating from a local shop and it was only marginally higher than if I had used Mobile 1 full synthetic. In fact, I have nothing but full synthetic gear oil at my place since most of my vehicles require it in the differentials. That big ol' 11-1/2" AAM in the back of my wife's truck takes a whole gallon every 15K miles, and my truck will take 3-1/2 quarts in its rear axle.

 

Agreed.
10W30 for engine and transmission and ATF for the Transfer case

I personally prefer Redline MTL for my transmissions but the price per quart is a bit ridiculous.

 

i use this Pennzoil Synchromesh Manual Transmission Fluid $9 a quart. i use it over any other brand.

 

I know a few who report smoother shifting with Red-Line MT. That's what I run in mine.

What ever you decide to run, get enough for a few changes and plan on a few short interval changes to ensure a good fluid change. - if you do that you'll likely be way ahead of most on transmission service.

 

If I were going to use a gear oil it would be Royal Blue, Amsoil, or Redline, but all are a bit expensive compared to 10/30 Dino and the benifit does not seem to justify the price.
Maybe it's because I deal with older differentials, but all of the gear guys I know suggest Lucas non synthetic for differentials. ECGS which builds a ton of rear ends strongly suggests Lucas non synthetic for its builds, I dont know why, but it's what I've been told by them.

 

If I were going to use a gear oil it would be Royal Blue, Amsoil, or Redline, but all are a bit expensive compared to 10/30 Dino and the benifit does not seem to justify the price. Maybe it's because I deal with older differentials, but all of the gear guys I know suggest Lucas non synthetic for differentials. ECGS which builds a ton of rear ends strongly suggests Lucas non synthetic for its builds, I dont know why, but it's what I've been told by them.

Not sure really how cost effects your transmission fluid selection. Isn't the interval like 60k miles for a fluid change? Even if you do it more often - what's the real cost difference over the ownership of the jeep.

I can see it affecting your selection on the diffs. If you wheel and change your fluid a lot.

 

If the higher cost has a positive result it's well worth it, if it has no beneficial value then why pay more? My point is it's a waste of money to pay for fancy fluids, if you think it helps by all means pay the extra. Your choice really.

 

Hello the 10w30 oil is for 4 cyl?
thanks

 

Hello the 10w30 oil is for 4 cyl? thanks

4 Quarts 10w30 for a 4 cylinder engine

 

Engine: 10W-30 motor oil (I use Castrol high mileage part synthetic) - 4 qts puts you halfway on the dipstick
Tranny: 10W-30 full synthetic or GL-3 gear oil (I use Mobil 1)
Transfer case: ATF +4 for Chrysler vehicles (I use Castrol full synthetic)
Power steering: same as above

I'll scan my Haynes page soon.

 

I just did my tans fluid and engine oil. My ax5 trans took 3.5qts of pennz synchromesh and my 2.5l engine took 4.5qts too get halfway on the dipstick.

 

I just installed a reman ax15. Allstate gear recommended 75/90. Synthetic gear oil.. So thats i put in it!

 

How much was that reman? I'm looking into doing it, but have no clue how

 

As previously mentioned, I think Chrysler's 10w30 motor oil option for the transmission has more to do with a GL3/GL4 not being as commonly available. The Amsoil GL4 75w90 shifts better, especially in cold weather. The Pennzoil synchromesh is not really the correct fluid, it is a 5w30 viscosity.

 

Isn't the factory recommended lube for at least a 2012 Wrangler with a 6 speed manual transmission MOPAR MS-9224 5W30 Transmission Fluid?

 

Correct - Pennzoil Synchromesh meets the MS-9224 specification.

These are Aisin transmissions (AX-5, AX-15), not the German (Mercedes) built NSG-370 transmissions in the JK's, nor the American built NVG's like I have in our trucks. The lighter oil would be fine during the winster when they offer smoother shifting in cold temperatures, but for sustained high-speed driving in the summer months here in Texas... well. I wouldn't chance it.

 

I tried 30w, and I tried Redline MT-90

Here's what happened, I found the only store near me that sells Redline MT-90 and bought a gallon for my transmission. I got home, drained what was left in my tranny (it was definitely NOT enough in there), and opened the jug of MT-90, only to realize I had inadvertently grabbed a bottle of 75-90...not the right stuff, and here I sit with an empty tranny.

So, I pulled a jug of Castrol high mileage 10w-30 out and pumped it into the tranny. It worked just fine. I noticed a bit of a whine though, which I thought might be my planetary gear. Whatever, i drove it with the 30w for about 500 miles and then bought the correct Redline MT-90 today and swapped the fluids again.

I noticed a big difference in the smoothness of the shifting and my whine is almost gone. It's definitely a LOT quieter. Maybe my case is rare, maybe it's got something to do with the 'rinse' of 30w before adding the MT-90, but it did make a difference in my 1994 Wrangler with an AX-15.

 

Tell you what next time you need to change fluid try Amsoil Manual Transmission & Transaxle Gear Lube 75W-90 , I had previously ran MT-90 and it was so temperature tempermental I couldn't stand it... the Amsoil was a dramatic change.

 

Thanks for the tip, I'll keep that in mind, should I have any issues with this. I'm pretty happy with it, but I do hit some extreme temps; over 105 in summer, below 25 in winter. We'll see

 

An update to my last post in this thread- going into first gear was stiff when I first replaced the trans oil. Now as it gets warmer(or something is happening to the oil) shifting into first gear is smoother, all the other gears were fine to shift after the oil change, so no big change there.