Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: weekendwarrior on September 19, 2005, 12:12:13 PM

Title: Gear oil or ATF
Post by: weekendwarrior on September 19, 2005, 12:12:13 PM

Everyone I talk to seems to disagree on what I should be running in my ax15 :?  So which is it Auto tranny fluid or Gear oil ?

Title: Gear oil or ATF
Post by: BlackYJ on September 19, 2005, 01:20:55 PM

GEAR OIL 75w-90 or 80w-90

However the t-case is ATF.

Title: Gear oil or ATF
Post by: redbull on September 19, 2005, 02:05:07 PM

I agree with BlackYJ, and so does Haynes and Chilton. Remember to use ATF+3 (Chrysler vehicles) in the T-Case.

Title: Gear oil or ATF
Post by: weekendwarrior on September 19, 2005, 09:05:07 PM

That's what I thought but the guy that rebuilt the tranny told me gear oil is the best way to kill the tranny :?

Title: Gear oil or ATF
Post by: Woolf on September 19, 2005, 09:26:12 PM

I had the tranny in my XJ rebuilt a few years ago by a shop in Edmonton and the guy told me the same thing, but after the initial fill with ATF I quickly changed my mind and since have always run gear oil.  The only thing that's ever killed a tranny for me has been water.

Title: Gear oil or ATF
Post by: 4low on September 20, 2005, 12:00:16 AM

There was/is a misconception sometimes that GL5 gear oil attacks the brass/bronze syncro's in the tranny's and causes them to fail, I remember reading all this hoopla on JU a long time ago, anyway, people were running ATF, GL2, etc.
After checking with a petroleum engineer, older GL-5 had an issue with "some" metals, but that's all been cured for many years.
GL2 doesn't have that issue, but it doesn't have the anti-foam properties (it's a low speed, high load lubricant)

GL5 all the way, and maybe some Moly additive, but that's about it.

My 2 cents :D

Title: Gear oil or ATF
Post by: weekendwarrior on September 21, 2005, 10:53:52 AM

I guess the common thought is gear oil :D  Is that what everyone runs in the winter too. I've heard that it gets to thick when it's cold :?

Title: Gear oil or ATF
Post by: BlackYJ on September 21, 2005, 12:01:48 PM

Look at your owner's manual is say gear oil.  I run it all year long and no problems.  If you are worried about it than go with synthetic.  I believe ATF is a lot better for heat and autos create a lot of heat

Title: Gear oil or ATF
Post by: weekendwarrior on September 21, 2005, 03:49:00 PM

Thanks for the advise. :D  Im gonna run gear oil.

Title: Gear oil or ATF
Post by: 4low on September 21, 2005, 10:13:34 PM

(I got this idea from another forum a few years ago)
In the winter all I do is switch the transfer case into Nuetral, and put the tranny into 3rd gear while the jeep warms up, usually after about 45 seconds or so it shifts allot better.

my 2cents

Title: Gear oil or ATF
Post by: redbull on September 23, 2005, 12:10:58 AM

Quote from: "4low"

(I got this idea from another forum a few years ago)
In the winter all I do is switch the transfer case into Nuetral, and put the tranny into 3rd gear while the jeep warms up, usually after about 45 seconds or so it shifts allot better.

my 2cents

Brilliant! That's a nice tip, I'm gonna try that.