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ax15 question

RyanM

RyanM

NAXJA Forum User
Location
va
this was a longg time ago, and no real problems but I want some opinions. When i first got my jeep it had like 70K on it. all records, oil evey 3K, and transmission serviced once or twice. i drained it when i first got it, red fluid. Obviously some idiot refilled the tranny with ATF. and alot of metal on the magnet. i refilled it with 75w90 valvoline, and again with syththic not long after that. It had the common grind going into reverse when i got it, still does it, i just put it in 4th first.

my question, how much damage could have been done inside on the gears and syncros and bearings, to be honest it seems like it has gotten better with time, esp. when i went to 4.88's. sometimes a grind in 3rd, and hard to getinto 1st immediatly after clutch ingage. thanks all for any insight or experiance.
 
Hard to say without actually driving the vehicle/seeing the trans. Using the correct fluid will help though. I run Red Line MT-90 which is a 75w90 weight synthetic oil supposedly formulated for transmissions like the AX-15 with bronze(?) components. I also add a 1/2 pint of LubeGuard manual trans suppliment (can give you napa p/n) and now it shifts like a honda.

Also, my trans mount was going out, causing the trans and shifter to twist and bounce, replacing that made for better operation. At 150k miles my clutch master cylinder/slave combination (I think you have the same one in your 96) became squeaky, gave a stiff pedal and made 1st or reverse engagements difficult. I believe it was jambing or siezed, not leaking fluid pressure. Replacement of this part solved my problem. This problem of not smoothly entering 1st/R is often a clutch hydraulic or linkage problem on any given vehicle which won't allow the clutch to completely disengage.
 
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A lot of damage could have been done and it depends how long it was in there. It seems that right now you just have a little grind so a good fluid might change it. Current gear oils like Mobil 1 synthetic, Valvoline etc... that you buy at Kragen, NAPA, etc... are made mainly for differentials not transmissions. You can probably cure most of your grinding with a really good lubricant made for the manual transmission. I highly recommend Red Line MT90 http://www.redlineoil.com/products_gearlubricants.asp?pvID=74&prodID=57&subcatID=18 and the cheapest place to buy it that I have found is http://www.redlineoil.com/products_gearlubricants.asp?pvID=74&prodID=57&subcatID=18. This cured my occansial grind in my AX5 and in my friends Toyota ASIN tranny and makes shifting a lot smoother and easier.
 
BTW, reverse doesn't have a synchro. It's normal to grind a bit if you don't drop into a forward gear to stop the input shaft. Oh and before you slam the previous owner, some synthetic gear oils are red including RedLine MTL. I highly recommend a quality synthetic, too. Cheap off-the-shelf GL5 gear oil has lots of sulfurs which attack brass synchros and shorten their life. They also shift like crap when the tranny is cold. I used a mix of RedLine MTL and MTL90 in my AX15 and it made a world of difference.
 
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I owuldn't worry too much if it's working well now and has the right oil in it. When I got my 95 at 110 K it had GL5 in it, and made a lot of noise. Using the owner's manual as a guide, I replaced it with more GL5 and it made even more noise, and when I drained it a few thousand miles later the stuff looked like liquid gold. I put in Valvoline synthetic, and have not touched it since. It now has over 260K miles, shifts well, and makes less noise than it did at 110.
 
lawsoncl said:
Oh and before you slam the previous owner, some synthetic gear oils are red .
Click to expand...

i was thinking the same thing, but it was really thin. and it was too late to edit my post and i was looking for someone to say this

anybody know of anyother red gear oils

-----------
im going to switch to royal purple soon or redline. thanks guys
 
All the asin/warners need a GL3 rated gear lube, 5 years ago Mobil-1 75W90 was rated GL3/4, no longer, it is now rated GL5 which means it has sulphur in it, thats a show stopper for bronze sintered stuff. Your current options now are: Mopar GL3 AX15 tranny lube at $17 a quart, Redline MT's which was $11 a quart when I bought it 3 weeks ago at the local auto parts store and thats pretty much it. Lubes rated GL2/3/4/5 are lying, GL3= NO SUPLHUR, GL5=SULPHUR, you can't have it both ways, it either has it or it or not. Maybe one other, Amsoil synthetic, but even that says GL5 on the gallon my son has, he used it in his AX5 couple of months ago after the other tranny he had died a synchro death, he was too impatient to order and wait for the Redline an extra day..kids......
 
My bad the cheapest place I have found to buy Redline is here http://www.myoilshop.com/AutoPrds.html.
MT90 is $7.00 a quart shipping is reasonable for 6 quarts its $6.75 for FedEx ground. I recommend if you plan on running the Red Line to order their synthetic ATF Dextron II to put into the transfer case and the 75w90 synthetic gear oil to put into the differentials. You will save the most money if you buy it all at once from this place. You can search the internet but I tried and this is the cheapest place I have found. The ATF is $7.75 and the gear oil is $7.00 and the motor oil is $7.00. These are all really good prices on Red Line oil products.
 
tgoff said:
My bad the cheapest place I have found to buy Redline is here http://www.myoilshop.com/AutoPrds.html.
MT90 is $7.00 a quart shipping is reasonable for 6 quarts its $6.75 for FedEx ground. I recommend if you plan on running the Red Line to order their synthetic ATF Dextron II to put into the transfer case and the 75w90 synthetic gear oil to put into the differentials. You will save the most money if you buy it all at once from this place. You can search the internet but I tried and this is the cheapest place I have found. The ATF is $7.75 and the gear oil is $7.00 and the motor oil is $7.00. These are all really good prices on Red Line oil products.
Click to expand...

Actually GL5 is a good thing to use in differentials, the higher pressures take advantage of the sulphur in the lube. Thats what it was designed for.
 
I know thats why I recommended to run the Red Line 75w90 gear oil in the differentials and to run the MT90 in the transmission.
Transmission= Red Line MT90 (For AX5/AX15)
Differentials= Red Line 75w90 Gear Oil (For non locked/lsd, non tow rigs)
Transfer Case = Red Line Synthetic ATF (Yes, its a Dextron II/IIE/IID/Mercon. Perfect for the NP231/NP207)
 
tgoff said:
I know thats why I recommended to run the Red Line 75w90 gear oil in the differentials and to run the MT90 in the transmission.
Transmission= Red Line MT90 (For AX5/AX15)
Differentials= Red Line 75w90 Gear Oil (For non locked/lsd, non tow rigs)
Transfer Case = Red Line Synthetic ATF (Yes, its a Dextron II/IIE/IID/Mercon. Perfect for the NP231/NP207)
Click to expand...

Does it matter which Red Line ATF? Racing, high temp, etc? There are 5 choices of ATFs: Racing, D4, C+, Synthetic Dex II, High Temp. They are all about the same price $7.75-7.95/qt.

How many quarts of tranny fluid and t-case fluid are needed? I know both diffs together use like 3-4 qts (dana30/8.25).

I recently got a 98' 5 speed and want to go through all the fluids. I was thinking about adding Lucas, Royal Purple or other stuff, but you guys talked me into Red Line Products.

My 98' has a limited slip in the 8.25 and the RL 75/90 says is has the additive. What would I use in a detroit locked rig? My 91' is detroit locked f/r.

thanks,

Troy
 
over on my 300zx forum. alot of people run atf fluid in the 5-speeds. they say it tends to last longer and makes it shift better. i have seen no proof that atf fluid will damage a tranny. but this is the first.
 
90xj06 said:
over on my 300zx forum. alot of people run atf fluid in the 5-speeds. they say it tends to last longer and makes it shift better. i have seen no proof that atf fluid will damage a tranny. but this is the first.
Click to expand...

It may depend on the tranny, and unfortunately AX15's are a bit spendy to experiment on. Some manual transmissions are explicitly spec'ed for ATF. Both my old Mercedes 4-speeds take it. My old Peugeot 404 took plain old 10W-40 motor oil in its transmission, and shifted like a champ. I suspect that ATF would work pretty well in an AX15 too, but I'm not going to be the one who finds out if it doesn't! Not when synthetic gear lube works so very very well.
 
Big Red said:
...
How many quarts of tranny fluid and t-case fluid are needed? I know both diffs together use like 3-4 qts (dana30/8.25).
...
Click to expand...

My AX-15 took about 3.2 quarts (75W90 GL-3). I read on here that it should take 3.5 though... need to check it again when its good and cold. I drained it when hot, and refilled shortly after.

My NP231 took about 1.2 quarts (ATF).
 
Most fluid capacities (and recommendations from FSMs) are up in the "Tech Archive" section of my website - click the link and see! I'm also always collecting FSM's (I just picked up an 85...) for more information, so check back if you don't see your year listed already....

5-90
 
5-90 said:
Most fluid capacities (and recommendations from FSMs) are up in the "Tech Archive" section of my website - click the link and see! I'm also always collecting FSM's (I just picked up an 85...) for more information, so check back if you don't see your year listed already....

5-90
Click to expand...

Wow, very thorough Kelley you are quite the scientist. :) Now how much is a pint to a quart? You can get a quart and pint statement on the bottle when you pick up your fluids right? All that non American crap measurements :)
 
Big Red said:
Wow, very thorough Kelley you are quite the scientist. :) Now how much is a pint to a quart? You can get a quart and pint statement on the bottle when you pick up your fluids right? All that non American crap measurements :)
Click to expand...
:twak:

Pints are american. 2 per quart, learned that in first grade.
 
goodburbon said:
:twak:

Pints are american. 2 per quart, learned that in first grade.
Click to expand...

Thanks for the conversion. :)
 
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