AX-15 or Ax-5 Transmission Fluid Info

[Tex06]

Been having issues keeping her in first and found this on the jeepsunlimited.com (thanks to user marc1kim), thought it'd be useful to share.  This info is only for the Aisin (AX5/15 5 speed manual) transmissions, not the BA-10 or AW4:

 

*Pennzoil Syncromesh, and Royal Purple Synchromax are only recommended for the NV3550 and other NV trannys. (Not recommended for AX-5/AX-15).

*Pennzoil has a GL4 lube, and Royal Purple recommends 10W40 motor oil for all 98 and newer jeep manual transmissions WITHOUT the NV trans. (Ax-5/Ax-15 fall in this category) 

*10W30 and (Jeeps recommended) GL-3 are roughly the same viscosity, and Gl-4 and 10W40 same viscosity as well.

*All GL lubes have some kind of Sulfur content in them (needed for the High pressure Hypoid gears in rear ends, but not necessarily needed for most transmissions.)

*Sulfur addadives react to brass internal parts.

*GL-5 has twice the sulfur content of GL-4.

*AX-5 and AX-15 are japanese manual transmissions, and the majority of manual Japanese transmission do not recommend the use of GL-5. because of the way it reacts to brass.

*Red Line MTL is classified as a 70W80 gear lubricant satisfying the API Service requirements of GL-3 and GL-4. MTL also satisfies motor oil viscosities SAE 5W/10W/30, and the viscosity requirements for ATFs.

*Redline MT-90 is a 75W90 GL-4 and also satisfies motor oil viscosities SAE 10W/15W/40.


So it's safe to say:

AX-5/AX-15 can use (synthetic?) 10W30, 10W40, GL-4, Or Redlines MT-90 or MTL

and the New Venture transmissions Pennzoil Synchromesh, and Royal Purple Synchromax.

 

Allthough I searched many website Here are some references with some good info:

Good basic info and a mention of GL/ motor oil equivalents, and one mention of Japanese gear boxes.
http://en.wikipedia.org/wiki/Gear_oil

Viscosity chart:
http://www.bobistheoilguy.com/visc.html

Gear Lube Definitions:

http://www.finalube.com/reference_ma...tegories.h tm

Redline MTL / MT-90 info and what they can substitute:

http://www.roadraceengineering.com/p...-mtl-info.html

And from the Amsoil website:

"The difference in GL-4 and GL-5 is that GL-4 gear lubes have half the extreme pressure additives of GL-5. Because the gear types in manual transmissions do not necessitate the use of GL-5 gear lube, GL-4 is the correct recommendation called for by most OEM’s when gear lube is required."

GL-4 definition: "This designation denotes lubricants intended for axles with spiral bevel gears operating under moderate to severe conditions of speed and load or axles with hypoid gears operating under moderate speeds and loads." -

so GL-4 will have additives for the Hypoid Gears.



And here's where it all comes home (and probably explains why Chrysler made the change):

GL-3 Definition:

"Gear lubricants designated for API GL-3 service are not intended for axles with hypoid gears. Some transmission and axle manufacturers specify API Category "CC" or "CD" motor oils for this service."

note: "CC" and "CD" oils have been upgraded to newer designations and are equivalent to 15w40
 

[Tex06]

I'm gonna be swapping whatever is in mine with 10W-30 synthetic this afternoon....currently it shifts like a well-abused logging truck and kicks out of 1st if you shift into it at a stand still (but downshift while rolling and she'll take off just fine from a stop....go figure).  

 

 

 

Also, if you really, really want to get into the nitty-gritty of it this is a great little read. http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2554764

 

Turns out, not all GL-5 oils are bad for the brass....just some are.  It's difficult to know which ones though without out lab results (which these guys did!)

[88whitemanche]

I have 10w-30 conventional

In both my ax15 and ax5 with no issues...

[benjy_26]

Been running Oreilley's brand (just repacked Valvoline, I believe) synthetic 10-30 in my AX4 for almost two years now with zero issues. It really helped the shift feel, especially in the winter.

[FrankTheDog]

5 years 100k with Mobil 1 10w-30 HM.

[Eagle]

I thought it was time to settle this question, so I contacted the experts (HAH!) at Pennzoil to ask what to use in each of the available Jeep XJ and MJ transmissions. You all ain't a-gonna believe what they told me:

 

Hi, [___]:

 

For AX-4, -5, we recommend using 75W-90 GL-5 (1998-2002, they are recommending 75W-90

GL-3 instead).

For AX-15, we also recommend using 75W-90 GL-5 (1998-1999, they are recommending 75W-90

GL-3 instead).

For BA10/5, they are also asking for 75W-90 GL-5.

For NV 3550, we do recommend using Pennzoil Synchromesh.

 

 

For the 75W-90 GL-5 applications, we recommend our Pennzoil Platinum Axle 75W-90 GL-5.

We do not have any recommended products for 75W-90 GL-3 applications.

 

 

If you would like to speak on this subject or have any other questions, please give us a

call at 1-800-237-8645, option 3,2.

 

 

Regards,

Technical Information, hn

In summary, they referred to obsolete information that the Jeep factory superceded many years ago. NOT helpful.

 

Not a surprise they don't have any GL-3 products. They are, after all, gear oils. GL-3 was replaced in the marketplace by GL-4, which was in turn replaced by GL-5. So I guess the answer for the manual transmissions other than the NVG 3550 is either Redline or 10W30 motor oil (to which I would add a molybdenum disulphide additive such as Mr. Moly).

[Tex06]

Good call on the moly additive. Didn't think about that but it should help with wear.

 

Drove my MJ from NOLA to Birmingham to Chattanooga to Atlanta yesterday (yes, long day).

 

The ax15 seems to like the 5w-30 synthetic well enough around town (easier shifts, less noise, want popping out of 1st near as often ) but after being on the highway for a long period (3-7 hours) there's a lot more noise and shifting takes considerable effort. Especially noticed shifting out of 5th...almost like I'm not depressing the clutch. Oh and it kicks me out of 1st everytime. If it sits up over night, shifts like butter again.

 

At this point I know I'm going to rebuild the tranny so in going to try a couple different fluids once I he the Jeep back next month and see if there's any difference.

 

FWIW, I used super tech synthetic oil.

 

Sent from atop the porcelain throne.

[Megadan]

I ran Mobile synthetic 10w-40 during the first few thousand miles on my rebuilt AX-15. I switched to Redline MT-90 after that.  The difference between the two is very noticeable.  The motor oil works, but compared to the MT-90 it made the transmission louder, clunkier (harder to shift), and the heat through the trans tunnel (bare metal, no insulation) was more noticeable.  MT-90 is worth the money if you can spend it.  I won't run anything else.

[Tex06]

Good to know. I'll try redline next time

 

X2 on the heat. I forgot to mention that it gets pretty warm coming off the tunnel. Didn't do that before either.

 

Sent from atop the porcelain throne.

[Eagle]

Heat = friction = wear.

 

Since the Pennzoil Synchromesh isn't recommended, I'd go with the Redline.

[benjy_26]

I haven't noticed any undue amounts of heat coming through my un-carpeted floors with the 10-30 synthetic, but, I do have a 2.5 and I drive like a grandma.

[Megadan]

I haven't noticed any undue amounts of heat coming through my un-carpeted floors with the 10-30 synthetic, but, I do have a 2.5 and I drive like a grandma.

 My trans tunnel could get hot enough to slowly burn your leg if you had it resting against it.  Now it just gets warm.  Never really measured the heat, but quite a difference.

[benjy_26]

Ah...well, I have a bigger than stock exhaust near there, so any additional tranny heat would be unnoticeable.

[xjrev10]

Rotella in the engine, Rotella in the transmission.

 

(I have Royal Purple sync max in my nv3550)

[ComancheKid45]

Been running Syncromesh in my AX15 for a few years with no issues... However the truck its in only gets maybe 700 miles a year or so put on it anymore.