Has anyone rebuilt your AW4? Good or bad results?

[XJ Dreamin']

The AW4 is a fairly simple box - and a "Master" rebuild kit (including clutches, steels, and whatever) goes for about $300 locally, or a "Overhaul" kit (basically a reseal kit and components to renew the valve body) for about $90 - both at the tranny shop up the street from me here.

You will need two "special" tools that I was able to make from bulk stock - there are some very large snap rings (which won't work with standard snapring pliers - I made a part of "chopsticks" using 1/4" aluminum round rod and D&T for #4-40 setscrews) that worked well, and get a decent bit of barstock and some M10x1.5 and M8-something (I don't remember what) and some 1/2-20 allthread to make the bridge puller to pull the planetary sets out. If you need me to, I can probably dig them up and take digipix for you sometime in the next couple days.

Total cost for "special" tools - about $20, all up.

You MUST have a camera capable of giving you pictures straight away for any valve body work - since there seem to be a few revisions of what goes where, and the manual isn't always right. I should have the ATSG AW4 manual around here somewhere as a .pdf (it's the one I used - and I found it online somewhere. Probably at Strokers - groups.yahoo.com/group/strokers) which has everything else correct - I've just never trusted manual pix of valve bodies (and I'm usually rewarded for that lack of trust.)

The three valve body solenoids can be readily checked with an ohmmeter - as I recall, 13 +-3 ohms is nominal. Hopefully, they're fine - they're spendy to replace (and I haven't been able to build up a stock.)

With either renewal kit, you WILL have valve body gaskets left over - it's a kit for all AW4 variants (Celica, Supra, Pickup, Van, XJ, MJ, ...) and you will match the gaskets up against the old ones to select them.

Results? I did the transmission in my wife's 89 about 80Kmiles ago - no complaints.

5-90

Hey, 5-90. I've overhauled plenty of Chyco TorqFlites. That was always set the valve body aside and replace all clutch plates, seals, and gaskets. Given the needed "special tools" (my Dad never bought a special tool - always made his own), would you say an AW4 job is comparable, more technical or what? Just curious - in case I have to some day. Thanks.

 

[summitlt]

I have one out of a 1998. I can get pics if you want. Maybe compare connectors to see if it will work.

 

[96 Cherokee]

I have one out of a 1998. I can get pics if you want. Maybe compare connectors to see if it will work.

I was told by someone that a 98 AW4 would not work on a 96. I'll do some further checking into it.

Thanks

 

[jeepsrock]

In my opinion rebuilding trannys such as the AW4 is one of the worst things you can do. If you have the time, getting a junked tranny from the yard with low miles will have a better chance or runnin good than a rebuilt tranny with cheap and incorrect parts internally. THe Aw4 was a widely used tranny and finding one for usually under 300.00$ isnt that hard..

pete

 

[Mike1331]

Mine was rebuilt by some crap shack in San Jose before I bought it. That was a big selling point for me. But lately the aw4 has been giving me nothing but diarrea. It slips out of gear constatnly and never shifts into second properly unless I let off the gas accordingly.

 

[Mike1331]

oops sorry guys forgot I was searching through old threads didn't mean to bring it back just to bitch

 

[Johnny V]

This seems like a good deal:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7947661133

 

[xjtrailrider]

My Aw4 went out at 86k, lost down shifting into 1st. It turned out to be the shift solenoid for first gear. I had both shift solenoids replaced, it cost me $800(the solenoids were $250 each). I then installed a 30,000 GVW Hayden tranny cooler and a B&M tranny temp guage. 14k and no problems and I tow a 3000# bass boat on a regular basis.

 

[CMNCHE]

Swap in a manual.

 

[lawsoncl]

I was told by someone that a 98 AW4 would not work on a 96. I'll do some further checking into it.
Thanks

The rear speed sensor on the 98 is different and will not work with the 96 computer as it puts out 4 pulses/rev and the 96 computer is expecting 1 pulse/rev. The 98 also has an input shaft speed sensor that is not found on the 96. The wiring harness connectors are different as well.

With all that said, it is still possible to use the 98 tranny. You can cut and splice wiring as needed and ignore the front sensor. If you have the 96 tranny, I believe you can pull the rear housing off and swap the output shaft rotors and use the 96 sensor. I have a 99 AW4 in my 89, but since I started with an AX15 and didn't have the right parts, I built an electronic box to convert the rear shaft sensor signal. Everything else bolted right up.

 

[96 Cherokee]

The rear speed sensor on the 98 is different and will not work with the 96 computer as it puts out 4 pulses/rev and the 96 computer is expecting 1 pulse/rev. The 98 also has an input shaft speed sensor that is not found on the 96. The wiring harness connectors are different as well.

With all that said, it is still possible to use the 98 tranny. You can cut and splice wiring as needed and ignore the front sensor. If you have the 96 tranny, I believe you can pull the rear housing off and swap the output shaft rotors and use the 96 sensor. I have a 99 AW4 in my 89, but since I started with an AX15 and didn't have the right parts, I built an electronic box to convert the rear shaft sensor signal. Everything else bolted right up.

Thanks for the info. I have run across several '98s, but no '96s yet. I'll check with my man and ask if he thinks he can do the swap.

 

[Menzenski]

Swap in a manual.

x2. Driver-controlled > computer-controlled.

 

[96 Cherokee]

x2. Driver-controlled > computer-controlled.

While I agree there are advantages to a manual transmission, working a rural mail route is not one of them. I'll have to stick with the automatic.

 

[pressurerat]

Can anyone explain exactly why an AW4 is not a good candidate for a home rebuild? Other than the need for simple special tools, that is to say.

 

[jeepsrock]

I am not trying to discourage you or anything nor be repetitive but i dont see why you would rebuild a tranny that seems to last a long time to begin with-- If you could find a cheap low mileage used one i think that would be your best bet. Most rebuilt AW4 i have seen either dont last very long or just dont work right. Now if you have the knowledge and time to do it yourself and you enjoy it then what the heck.

pete

 

[lawsoncl]

I too have seen a number a posts on where people complained about rebuilds not lasted. I don't know if the issue is really about a poor rebuild and possibly using the wrong fluid, or maybe that the original and subsequent problem was electronic and not mechanical at all. I suspect some of the fly-by-night tranny places are installing the $100 overhaul kit and not the full $250 rebuild kit.

 

[scoobyxj]

I too have seen a number a posts on where people complained about rebuilds not lasted. I don't know if the issue is really about a poor rebuild and possibly using the wrong fluid, or maybe that the original and subsequent problem was electronic and not mechanical at all. I suspect some of the fly-by-night tranny places are installing the $100 overhaul kit and not the full $250 rebuild kit.

I have noticed this myself, but can't understand why. As 5-90 stated the AW-4 is a farly simple tranny for it's day. I gess the issues just come down to tolorences, and specs. If you don't get them perfict it's pointless. Knowing that it's a Toyota derived unit I would take it to a Toy dealer for tranny work.

 

[pressurerat]

I agree with replacing with a used low miler before rebuilding, but the good used ones wont be around for many more years. I was just wondering what wore out; does the case itself lose tolerance and wear, or is it like other older automatics? I have had good luck with the old stuff like GM TH350's, Mopar999's, and manuals trannys, but have never messed with a 'computer controlled' automatic transmission. I am no pro, but do have some knowledge of the field.

 

[Justin Tyme]

Well, I dont mean to bring up an old thread, expecially as my first post on here but, I am thinking about rebuilding the aw4 in my '90. I have rebuilt a good hand full of manual trannies(mostly Mitsubishi's) and auto trannies(mostly TH350s) and wondering why so many people cant seem to get an AW4 to work well or long after rebuilding it. Also, where can I find a servie manual or VFAQ or something to help me through the proccess to make sure I get everything with-in spec. I have the one that is in the truck now and it acts as if the pump is going out. Then I have one in the garage that was having some shifting problems before it got pulled and the rest of the Jeep got parted out and scrapped. So, I either need to rebuild the one in the garage and then swap it out or just buy a known good one or maybe a brand new one from just4jeep on eBay for $1125 shipped. Let me know what you guys think to help me descide what I am going to do.

Thanks in advance,

Justin

 

[5-90]

Hey, 5-90. I've overhauled plenty of Chyco TorqFlites. That was always set the valve body aside and replace all clutch plates, seals, and gaskets. Given the needed "special tools" (my Dad never bought a special tool - always made his own), would you say an AW4 job is comparable, more technical or what? Just curious - in case I have to some day. Thanks.

I haven't done very many Torq-Flites, but I'd rate the AW4 as easier than a THM350/400, once you have the "special tools" (which can really be made - the only things I had to make for the job were the bridge puller and I made a pair of "snap-ring chopsticks" for the one or two VERY large internal snaprings - just use some aluminum round rod (I think I used 1/4",) drill and tap for #4-40, and use a couple of headless setscrews. Leave about 3/16" to 1/4" of the screws sticking out - that's what you'll grap the holes in the snapring with.)

If you can't find the ATSG service manual online anymore (I think I got mine from Pirate,) let me know and I can email you a copy.

5-90