Opinions on replacing AW4 transmission fluid - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Cherokee & Comanche Forums > XJ Cherokee Technical Forum > Opinions on replacing AW4 transmission fluid

RIGID LED Light Blowout Sale - All Sizes, All Series, all ECGS Black Friday Sale!!6th Annual, Beat Your Wife to the Credit Card Sale!

Reply
Unread 02-03-2009, 12:49 PM   #1
87warrior
Registered User
2003 TJ Wrangler 
 
Join Date: Sep 2004
Location: Junction City, Kansas
Posts: 1,605
Opinions on replacing AW4 transmission fluid

I finally have a Jeep with the AW4 transmission and have a concern. It is in a '92 with 185k on the odometer. Due to the fact the truck is 17 years old I am planning a fluid change for everything.

Should I change the fluid/pan filter in the AW4? If so, with what?

I recall that some folks suggest not to change the ATF in an auto with a lot of miles on it. Please school me on this.

Thanks

__________________
03 Rubicon(Rubicon build)
92 Comanche (92/99 Comanche Project)
86 Comanche (Heavy Four)
87warrior is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 02:03 PM   #2
98muddyjeep
rockin lil red wagon
 
98muddyjeep's Avatar
1998 XJ Cherokee 
 
Join Date: Jun 2008
Location: Hatboro PA
Posts: 1,228
you should be ok changing the fluid and filter since when you drain the pan you only get half the fluid the other half is in the converter so the new fluid will mix with the old so you will be ok.Do not get a trans flush that can cause more problems than its worth.
__________________
ah,beer the cause of and cure to all of lifes problems ...Homer J Simpson... I am the guy in the red jeep!
98muddyjeep is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 03:14 PM   #3
Jason, aka: Jeepin.com
Vendor
 
Jason, aka: Jeepin.com's Avatar
1995 XJ Cherokee 
 
Join Date: Mar 2002
Location: Lewisville, TX
Posts: 7,188
Quote:
Originally Posted by 98muddyjeep View Post
you should be ok changing the fluid and filter since when you drain the pan you only get half the fluid the other half is in the converter so the new fluid will mix with the old so you will be ok.Do not get a trans flush that can cause more problems than its worth.
Ditto on all of the above.

Changing the filter is a bit of a paradox though. I don't think I've ever read where someone's changed the filter and looked at it and thought that it needed to be replaced, but at the same time, everyone, myself included, has always felt better having replaced the filter, even if it looked perfectly fine.

Some places are now offering a non-pressure flush, where the transmission itself cycles all the fluid -- it's not forced through under pressure. That's the only type of "flush" I'd ever consider doing, and you can do that yourself with a couple of buckets and a bunch of fluid.

Be sure to use Dex/Merc III type fluid and nothing else. It may be a "Chrysler" vehicle, but it does not have a Chrysler brand transmission.
__________________
Jason West - Jeepin.com | JeepinOutfitters.com
'09 JKUR, RE 3.5", 37" GY MT/R-Ks, Expedition One bumpers, T&T rockers & skids, XRC10 Comp
'95 XJ, RE 5.5", 35" MT/Rs, D30 w/hubs & ARB, D44 w/Detroit, 4.56s, C4x4 bumpers, etc, etc.
'00 TJ, SOLD, wife's, RE 4.5" long-arm, 35" MT/Rs, D30+OX, D44+ARB, 4.88s, full cage, winch, C4x4 & Jeeperman bumpers, etc, etc.


Jason, aka: Jeepin.com is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 03:24 PM   #4
kadetklapp
Registered User
1997 XJ Cherokee 
 
Join Date: May 2008
Location: Indiana
Posts: 1,305
Quote:
Be sure to use Dex/Merc III type fluid and nothing else. It may be a "Chrysler" vehicle, but it does not have a Chrysler brand transmission.
Chry Co doesn't manufacture the AW4? Hmm, didn't realize that.

I use Dex/merc anyway.

What I have done with my 99 XJ is simply change it frequently using the handy-dandy drain plug. I gleefully use it as most all my mechanical experiance is with Chevrolets and in most cases you have to drop the pan on them. It's a real PITA.

Last summer when I bought my XJ the fluid was nasty, but the trans shifts fine. I went ahead and changed the fluid six times over the course of the late summer and early fall. In some cases I even got in the XJ and for a VERY short period of time would start it up and allow the pump to force some more fluid into the pan. I brightened the shade of red considerably using this process, and I never had to lower the pan.
__________________
**1997 Jeep Cherokee SE**
Former Police Car

2008 "Jeep" Patriot <-----Crap.
kadetklapp is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 04:09 PM   #5
Jason, aka: Jeepin.com
Vendor
 
Jason, aka: Jeepin.com's Avatar
1995 XJ Cherokee 
 
Join Date: Mar 2002
Location: Lewisville, TX
Posts: 7,188
Quote:
Originally Posted by kadetklapp View Post
Chry Co doesn't manufacture the AW4? Hmm, didn't realize that.
Nope. The AW4 is made by Aisin AW (though it ceased to be called Aisin-Warner in 1987, coincidentially the same year that Jeep started using the transmission, and is now just Aisin AW). If anything, it's a "Toyota" transmission because it shares a lot of parts with the Toyota 450-43LE that was used in I think the Supra and 4Runner. Toyota also owns a majority stake in the company, but Aisin AW provides transmissions to just about every car maker.

http://en.wikipedia.org/wiki/List_of..._transmissions
__________________
Jason West - Jeepin.com | JeepinOutfitters.com
'09 JKUR, RE 3.5", 37" GY MT/R-Ks, Expedition One bumpers, T&T rockers & skids, XRC10 Comp
'95 XJ, RE 5.5", 35" MT/Rs, D30 w/hubs & ARB, D44 w/Detroit, 4.56s, C4x4 bumpers, etc, etc.
'00 TJ, SOLD, wife's, RE 4.5" long-arm, 35" MT/Rs, D30+OX, D44+ARB, 4.88s, full cage, winch, C4x4 & Jeeperman bumpers, etc, etc.


Jason, aka: Jeepin.com is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 04:30 PM   #6
kadetklapp
Registered User
1997 XJ Cherokee 
 
Join Date: May 2008
Location: Indiana
Posts: 1,305
Wow I'll be darned!! Must be why the label on mine says something about Japan....
__________________
**1997 Jeep Cherokee SE**
Former Police Car

2008 "Jeep" Patriot <-----Crap.
kadetklapp is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 04:52 PM   #7
Jason, aka: Jeepin.com
Vendor
 
Jason, aka: Jeepin.com's Avatar
1995 XJ Cherokee 
 
Join Date: Mar 2002
Location: Lewisville, TX
Posts: 7,188
Heh-heh, it's somewhat ironic that something considered one of the most bullet-proof parts on an XJ is actually made in Japan.
__________________
Jason West - Jeepin.com | JeepinOutfitters.com
'09 JKUR, RE 3.5", 37" GY MT/R-Ks, Expedition One bumpers, T&T rockers & skids, XRC10 Comp
'95 XJ, RE 5.5", 35" MT/Rs, D30 w/hubs & ARB, D44 w/Detroit, 4.56s, C4x4 bumpers, etc, etc.
'00 TJ, SOLD, wife's, RE 4.5" long-arm, 35" MT/Rs, D30+OX, D44+ARB, 4.88s, full cage, winch, C4x4 & Jeeperman bumpers, etc, etc.


Jason, aka: Jeepin.com is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 05:07 PM   #8
justanotherjpr
Registered User
 
Join Date: Nov 2007
Posts: 6,337
By the time you have the pan down and the filter out, you should be replacing the filter. It's cheap and the cost of the fitler and gasket kit isn't a whole lot more than the cost of just the gasket, if you can even get it. Use only Dex III in the AW4. May consider the transmission pump flush, but, as Jason said, do not use any machine that flushes under power.
__________________
Quote:
Originally Posted by Motorcharge View Post
So do you actually hear your thoughts in your head or is it just sort of a dull roar before you smash your face into your keyboard and just submit whatever dumb **** ended up on the page?
justanotherjpr is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 05:43 PM   #9
tjwalker
It's the crank sensor!
 
tjwalker's Avatar
1999 XJ Cherokee 
 
Join Date: Nov 2007
Location: Central Minnesota, MN
Posts: 8,497
Quote:
Originally Posted by 87warrior View Post
I recall that some folks suggest not to change the ATF in an auto with a lot of miles on it.
I've heard that before as well and I couldn't disagree more with it. It defies logic to leave old, dirty, worn out, burnt tranny fluid in a vehicle.

The AW4 has a drain plug on it. You can change out approx. 3 quarts of fluid by just draining the pan. Do it a few times over the next few months if the fluid looks bad or smells burnt.

If you're ambitious, drop the pan and clean or replace the filter which is basically just a screen. Most important thing though is to get some fresh fluid circulating.

Use Dex III fluid.
__________________
99 Cherokee, 4.0 AW4, NP242
Past Jeeps: 49 Willys, 81 Scrambler, 88 Comanche
Without "data", all you have is an opinion!
tjwalker is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 08:12 PM   #10
87warrior
Registered User
2003 TJ Wrangler 
 
Join Date: Sep 2004
Location: Junction City, Kansas
Posts: 1,605
Thanks for the help guys. This whole Auto thing has me running in circles!

Should the Dex III/Merc III fluid available at the local auto parts store? I know synthetic is deemed a "no-no" on a high mileage AW4.

I think initially I will simply drain and replace the fluid. After 6 months I will replace the filter and fluid.
__________________
03 Rubicon(Rubicon build)
92 Comanche (92/99 Comanche Project)
86 Comanche (Heavy Four)
87warrior is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 08:20 PM   #11
Jason, aka: Jeepin.com
Vendor
 
Jason, aka: Jeepin.com's Avatar
1995 XJ Cherokee 
 
Join Date: Mar 2002
Location: Lewisville, TX
Posts: 7,188
Dex/Merc III is a regular trans fluid, it should be available anywhere that sells vehicle fluids.
__________________
Jason West - Jeepin.com | JeepinOutfitters.com
'09 JKUR, RE 3.5", 37" GY MT/R-Ks, Expedition One bumpers, T&T rockers & skids, XRC10 Comp
'95 XJ, RE 5.5", 35" MT/Rs, D30 w/hubs & ARB, D44 w/Detroit, 4.56s, C4x4 bumpers, etc, etc.
'00 TJ, SOLD, wife's, RE 4.5" long-arm, 35" MT/Rs, D30+OX, D44+ARB, 4.88s, full cage, winch, C4x4 & Jeeperman bumpers, etc, etc.


Jason, aka: Jeepin.com is offline   Reply With Quote Quick reply to this message
Unread 02-03-2009, 08:55 PM   #12
jjg214
Registered User
2001 XJ Cherokee 
 
Join Date: Dec 2008
Location: Long Island NY
Posts: 1,080
why shouldnt synthetic dex/merc be used on a high mileage AW4?
jjg214 is offline   Reply With Quote Quick reply to this message
Unread 02-04-2009, 06:31 AM   #13
jjg214
Registered User
2001 XJ Cherokee 
 
Join Date: Dec 2008
Location: Long Island NY
Posts: 1,080
Quote:
Originally Posted by 87warrior View Post

Should the Dex III/Merc III fluid available at the local auto parts store? I know synthetic is deemed a "no-no" on a high mileage AW4.
anyone have a reason for me?
jjg214 is offline   Reply With Quote Quick reply to this message
Unread 02-04-2009, 08:28 AM   #14
tjwalker
It's the crank sensor!
 
tjwalker's Avatar
1999 XJ Cherokee 
 
Join Date: Nov 2007
Location: Central Minnesota, MN
Posts: 8,497
I have used synthetic transmission fluid (Amsoil) in my AW4 since the first service. I also use synthetic fluids in the differentials and transfer case. You will find many differing opinions on this. In my opinion, there isn't a right or a wrong answer.

There are people that claim that the synthetic fluid is actually "too slippery" for the AW4 but I haven't seen enough actual failure analysis to support that claim. Just because a transmission fails early and that individual was using synthetic doesn't necessarily mean that synthetic fluid was "root cause" of the failure. A certain percentage of anything as complex as a transmission will suffer premature failure no matter what fluid is circulating in it.

The AW4 certainly doesn't require a synthetic; plain old Dex III is much cheaper and works just fine with plenty of evidence of AW4 transmissions going 200-300k on conventional fluids.

However, there are a number of reasons that people "choose" to use a synthetic. To each their own. Use the SEARCH function for tons of light reading on this. No need to reinvent the wheel.
__________________
99 Cherokee, 4.0 AW4, NP242
Past Jeeps: 49 Willys, 81 Scrambler, 88 Comanche
Without "data", all you have is an opinion!
tjwalker is offline   Reply With Quote Quick reply to this message
Unread 02-04-2009, 09:22 AM   #15
kadetklapp
Registered User
1997 XJ Cherokee 
 
Join Date: May 2008
Location: Indiana
Posts: 1,305
I use plain Dex/Mex just because it's plentiful and cheap.

Some people believe that putting fresh fluid in an old transmission causes it to fail. The fact is, if the trans is slipping after fresh fluid, then the trans has been on it's way out for a LOOONG time. If it does slip, and you need to get a little more life out of it, then you can use a friction modifier in the fluid to help get "grip."

That's all it is. The old gritty fluid causes the stripped transmission to get better "grip" and when new fluid is injected, it starts to slip.
__________________
**1997 Jeep Cherokee SE**
Former Police Car

2008 "Jeep" Patriot <-----Crap.
kadetklapp is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.