Bulletproof AW4?

OneTonXJ said:
I want photographic and possibly movie proof that this thing runs under its own power. :wave:
235.jpg

DSCF0730.JPG


imagine that! :laugh3: pics from their run here, looks like Jes went too: http://www.rps4wd.com/cgi-bin/yabb/YaBB.pl?board=chat;action=display;num=1111849841




Sean, just run a BIG cooler and don't run it through the radiator, just the aux. cooler. the AW4 is up to the task with the right cooler.
 
Big cooler.

Deep snow and deep sand kill anything that slips to bias torque, converter based trannys and limited slip diffs. The AW4 needs a larger cooler if you want to flog it in the converter slip rpm range. Even choosing a low gear, low range, to keep the converter fluid flow and rpm high will not always keep the trans fluid cool (because the engine temp increases, but it can help).

The AW4 filter is more a debris screen, than a filter. The magnet(s) in the bottom of the pan collect the metal shavings while the screen sifts out the large clutch pad wear chunks. The screen will get clogged with high mileage soft chunks, starving the trans of fluid volume (and pressure). Change the fluid and wash out the filter/screen, and the grit stuck to the pan magnets.
 
Anyone want to post up the part number on the replacement filter on the AW4?

I've had mine serviced numerous times.....never replaced the "filter". We did clean off the screen, however.

:D
 
For those who drain their own fluids, what do you do with the old tranny fluid? Can it be recycled like regular oil? Just mix it in with old oil and recycle it together?


Okay, back to tech... :laugh3:
 
i just have a big 5 gal container that gets everything PS fluid, gear oil, trans, engine oil etc. i drain it at autozone when it gets full

:repair:

i dont think they care too much
 
Pretty much everything from transmission fluid to grease uses the same base - just different viscosities - so you can recycle it all together. I do, and I have no trouble with it (grease is really little more than a VERY heavy oil - and the same goes for asphalt, actually...)

There is a sump screen in the AW4. It doesn't usually need replacing, I just clean mine out every 100K miles or inspect it if I think something is amiss. Never needed to replace the thing...

TIP - drain the fluid over a magnet in the drain pan. The magnets in the transmission sump get "fuzzy" after a while, and they won't pick up as much. The magnet in the drain pan will let you know if this is so, and if you should clean the magnets in the pan. If you drop the pan, clean the filter and the magnets. A regular change should just require you to pull the plug.

If you find it necessary to pull the pan, don't try to take the dipstick elbow out of the pan - just pull the dipstick tube apart a little above the elbow. There's an o-ring join there, but I don't have measurements on the ring handy (although I remember it being fairly common.) Lubricate with a little grease on reassembly.

The issues with synthetic in the AW4 seem to stem from high mileage - most people who do a break-in of 5,000-25,000 miles and switch don't have any trouble, but people who switch after 100,000 miles or so seem to have the failures and silliness we don't like. I ran a thread on transmission fluids recently, search it up and have a look. Simply put, if you have some mileage, you're better off staying with the regular stuff since that's what the box is "used" to.

Treated well and kept cool, you'll find that the AW4 will give you excellent service life.

As far as the RWD Toyota mods - same box. Gotta look into those myself sometime... Got links?

5-90
 
Goatman said:
Anyone want to post up the part number on the replacement filter on the AW4?

I've had mine serviced numerous times.....never replaced the "filter". We did clean off the screen, however.

:D


Yeah thats part number 0Ithoughtthescreenwasafilter. When i did mine last on my 88 i bought a new screen. Did i throw money away? Im changing my 99's fluid at the end of this week so should i just wash off the screen and the magnets? Also, i found it better to let the tranny drain overnight b/c it dropped like another half quart overnight. Then i reinstalled and filled. Only this time it's my DD so i dont have time to let it not drive for a day.

-Mike
 
LouisianaZJ said:
do NOT run synthetic as suggested above :sunshine:
I was thinking of putting Redline ATF in my AW4... but I Think thats synthetic..

Thanks I tend to put synthetic fluid in everything if I don't have a good reason why not to :)

I guess I'll read the above thread... :)

I'm at 144K miles..
 
Last edited:
Goatman said:
Anyone want to post up the part number on the replacement filter on the AW4?

I've had mine serviced numerous times.....never replaced the "filter". We did clean off the screen, however.

:D

Both mine use a spin-on NAPA Gold (Wix) 1068 :laugh3: Motorcraft FL1A and AC PF2 work in a pinch.

Like Ed and others have said, run as big a cooler as you can physically fit. I divorced the fluid from the radiator with no obvious ill effects. YMMV. Factory AC condensers work good since they are fairly big, already have solid mounting provisions, and still allow room for an additional aux cooler (for engine oil or PS fluid.) I added a spin-on filter to the cooler circuit.

Before I went this route, I thought I 'smoked' my AW4 (it was Easter weekend, two yrs ago...) it was a NTL mudfest at Uwharrie - steep clay hills. after a good deal of abuse, my junk developed the "go-no-mo" slippage syndrome. Had to get Bigwoody/Greg to tug me up & over the top of the hill, where I parked to watch the other fools try some "slickrock." After 30-45 min of sitting/cooldown, my junk was unjunky for the rest of the weekend. I did change out that fluid as soon as we made it home, and the tranny has shown no ill effects or ever slipped like that since. All I use is 'house brand' Dex/MercIII in my AW4s.

Maybe the 'no synthetics' in the AW4 really is a wives tale, but I'll probably be sticking with what I've known to work.
 
today I had a long conversation with a guy at a tranny shop here in windsor that does alot of the "big 3" R+D/ audits of they're tranny's.

I went in looking for a shift kit and he confirmed that the tranny is actually a toyota tranny and the thing is tough as nails. and does not need a shift kit to hold up to the power of any jeep I6 (including strokers) w/ up to 35" tires

he did reccomend a cooler placed in line between the tranny (output) and the stock cooler in the rad. the logic being the hot fluid is cooled in the cooler then warmed backup to operating temp by the in rad cooler, thus keeping the fluid right in the proper temp range.

he also said with 4 wheeling and all it would be a good Idea to change the fluid every year and as long as the fluid stays clean there would be no real need to go up to synthetic.

he also said that if you ever do destroy a tranny there are so many XJ's out there that just getting another would be the way to go.
 
BLSXJ said:
today I had a long conversation with a guy at a tranny shop here in windsor that does alot of the "big 3" R+D/ audits of they're tranny's.

I went in looking for a shift kit and he confirmed that the tranny is actually a toyota tranny and the thing is tough as nails. and does not need a shift kit to hold up to the power of any jeep I6 (including strokers) w/ up to 35" tires

he did reccomend a cooler placed in line between the tranny (output) and the stock cooler in the rad. the logic being the hot fluid is cooled in the cooler then warmed backup to operating temp by the in rad cooler, thus keeping the fluid right in the proper temp range.

he also said with 4 wheeling and all it would be a good Idea to change the fluid every year and as long as the fluid stays clean there would be no real need to go up to synthetic.

he also said that if you ever do destroy a tranny there are so many XJ's out there that just getting another would be the way to go.
Actually the AW4 is not a Toyota tranny, it is manufactured by Aisin Warner and used by Jeep, Toyota, Isuzu, Mitsubishi, Nissan, BMW, Volvo... and possibly more. There are 3 Jeep versions (Renix, HO, and 2.5 engines) at least 3 Toyota versions, and likely many others between the other companies using them.

I see no reason why he should make any mention of a tire size limit. The tranny is only affected by the power input to it by the motor. I would have no suspicions of breakage if someone wanted to use an AW4 behind a stroked 4.0 followed by adequate gearing and 53" Michelin tires. The AW4 in stock form is sufficient for up to 400hp, so even a stroked, supercharged 4.0 would likely be fine or a mildly built 304. Further upgrades can be had from Level Ten, but open your wallet wide.

An auxillary cooler is a great idea for any AW4 imo. If you keep the fluid cool and water out, there is no need to change the fluid every year. I also agree that AW4s are not worth rebuilding, 87-90 versions are often free and it isn't hard to find a 91+ with under 100k miles for under $200.
 
woody said:
Both mine use a spin-on NAPA Gold (Wix) 1068 :laugh3: Motorcraft FL1A and AC PF2 work in a pinch.

I added a spin-on filter to the cooler circuit.


:laugh:

Cute, Woody.... :)

Running the fluid through the radiator after the cooler is probably a good idea.....never thought of it that way. I bypassed the radiator to help the engine cooling a little figuring it wouldn't hurt to isolate the small amount of heat from the trans. Luckily, our beloved XJ/MJ's have very durable motors and trannies. Allows for the $$ to be spent on other stuff...... :D
 
Thanks for the responses. I am going to order the biggest cooler that I can. I haven't yet inspected the fluid from saturday. The good news in all this is that I am slowly making my XJ a non-trailer queen.

SeanP
 
Sean, I just used a medium sized Hayden from Pep Boys.

Once the fluid gets hot (even just once) it looses it's important properties, so it needs to be changed or it will eventually damage the tranny.
 
Sounds like a good upgrade...

Where's the common spot to place the bigger cooler?

I had a co-worker a few years back that added a tranny cooler to his 'yota and bolted it to the underside of his hood and made a vent right above it...

IIRC he just had enough slack in the line to allow the hood to open/close...

bad idea?
 
Just mount it in front of the radiator, in front of the mechanical fan. When you buy the cooler it comes with the necessary pieces to mount it and hook it up.
 
some awesome upgrades to a aw4 ive seen is a larger oil pan, held 2 more quarts of fluid then a reg

and that combined with a good tranny cooler will save years on any auto tranny
 
Back
Top