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Aw4 power handling/ reliablity and performance upgrades.

There are also modifications that can be done to the PCM to firm up shifts. When I had my PCM flashed they turned torque management off and turned stall torque off. This resulted in firmer shifts and a more connected feel. I am not 100% what these features do, but since its in the PCM (not TCM) I would think that TCM sends a signal to the PCM to reduce engine output during shifts.

interesting... you have more info on the flash?
 
One of the clutch pistons is thinner in the Supra A340e due to a slightly shorter bellhousing and different TC. Some of the kits that upgrade the Supra trans include a billet piston. I'll upload a pic later. The Lexus version (and our Jeeps) have a thicker piston and don't require the billet version until you are trying to go over 700+, which I wonder if the 4.0L is even capable of holding that anyway.
 
awesome thanks for the info guys. i really wanna get this motor singing since its fairly low miles and possibly throw some boost on it.

i loev the aw4 but it sure does soak up power, this thread is fantastic. i'll def be doing tranny mods in the near future.
 
subscribed!

Any write ups on how to do any of this stuff, rebuild, valve body pics? I know little to nothing about trannies :D
 
It may be better to use a JDM A340e from a Toyota Aristo (2JZGTE powered Lexus GS300). It is even closer to the Jeep AW4 than the Supra version.
Theres two versions of the A340E. The ones in TT setups are way different then the AW4. The A340E's in N/A cars,trucks, suvs, is most closely related to the 23 spline AW4. Same solenoids, same amount of clutches, etc, etc.


It's not only your first sticky it's the first sticky for the Street and Performance forum.

If you have the money and go with the IPT parts you might as well send in your old torque converter to be customized. I'm currently sitting on an IPT rebuild kit and and just moved into a place with a garage maybe I’ll start building up my spare transmission.
It is the first sticky here. Thats awesome. Also, can you possibly email me some pics of the IPT rebuild kit? [email protected]. I really want to see the clutches and that (c-2 clutch pack). The pic on their site just doesnt do justice.

So happy to help - and I could hear you giggling all the way over here...

If it makes you feel any better, I was halfway considering sticking this thread before I read CherBear's post - once I saw that, it pulled me off of the fence.
Hey I'm glad you did make it a sticky, if people actually read the write up and follow the links that I posted they can learn alot of info.

i'm def interested in building/getting a faster shifting aw4 in the future.
If you read my original post theres a link to a write up on placing shims in the accumilators to reduce shift times. Make sure to read the whole write up and then try it. Theres guys who claim after they did it, thier A340E's shift faster then their manual counter parts.

Any write ups on how to do any of this stuff, rebuild, valve body pics? I know little to nothing about trannies :D
I didnt find any write ups on rebuilding the valve body, but the shimming of the accumilators has a link posted up.
 
Theres two versions of the A340E. The ones in TT setups are way different then the AW4. The A340E's in N/A cars,trucks, suvs, is most closely related to the 23 spline AW4. Same solenoids, same amount of clutches, etc, etc.



It is the first sticky here. Thats awesome. Also, can you possibly email me some pics of the IPT rebuild kit? [email protected]. I really want to see the clutches and that (c-2 clutch pack). The pic on their site just doesnt do justice.

Hey I'm glad you did make it a sticky, if people actually read the write up and follow the links that I posted they can learn alot of info.

If you read my original post theres a link to a write up on placing shims in the accumilators to reduce shift times. Make sure to read the whole write up and then try it. Theres guys who claim after they did it, thier A340E's shift faster then their manual counter parts.

I didnt find any write ups on rebuilding the valve body, but the shimming of the accumilators has a link posted up.


you are awesome! The community thanks you!
 
Here is a link to my rebuild http://naxja.org/forum/showthread.php?t=962764 It's not a step-by-step but gives some good pictures of the inside. I can take some pictures of the IPT kit but i'm still working on moving so it may be a week or so.
 
I was reading back over this since I'm in the middle of the "soft overhaul" of an AW4. As I understand, in the A340s the clutches are NOT the weakest point. In fact, they are not even weak. Raybestos "blues" are not necessary. The regular raybestos yellows are what is used in the Boost Logic built autos and they hold plenty of power. see http://www.boostlogic.com/?paged=2 The sprags are what breaks 9 out of ten times... and I just put the same sprags in this AW4 today that are in every BL trans... they look IDENTICAL to the sprags I took out of the AW4.
Every friction disk I removed from the stock AW4 was really dark grey. I replaced them with raybestos yellows. So far the stock frictions were also showing barely any signs of wear. I've done the forward and overdrive clutch packs so far.

I am really curious to know of any experiences anyone reading this has had with actual AW4 transmission failure and what it actually was that failed.

So far, between working with the guy who builds the BL trannys and my personally working on this AW4, it is looking like swapping the frictions out, replacing orings and seals (while you're in there) and proper valve body setup are the only keys to balancing both performance AND longevity in our automatic Jeeps. I am sure a $4000 transmission is simply not necessary, and I aim to prove that.

Any of you Jeepspeed guys be willing to test a trans? I should have everything completed in a month or two. :)
 
http://my.is/forums/f114/info-leading-cause-transmission-failure-elevated-power-levels-412569/

Here you go my man. Your more than welcome to hit up Jeff. He did my trans when I had a boosted IS3. Hows 600whp through the auto trans sound?:firedevil
Yes, yes she was a beast. But he makes/builds custom 3rd sprags & modifies the valvebody so your not smacking the rev limiter all the time. At least in IS/Gs's. People with 350-450whp would smack the rev limiter in 1-3rd gear with the "ebay valvebody upgrade". I wouldn't hit it at all unless my trans was far too hot & I was running 600whp lol. That says something about his work! This guy know his sh*t its well worth the read. Many many people with boosted is300's ask who's built my trans, how aren't you popping the limiter. Jeff's my answer every time. Hes a great guy, just kinda hard to get a hold of at first. Once you have his number though your golden! He will always call back/ txt back & doesn't mind shooting the sh*t & spreading his info!

And to be specific he built my trans & modified my valvebody until I wasn't smacking the limiter. Just floor it & go! But ya he built my trans 1 time & it never broke. After 2 years of 450whp daily & quite a few highway/drag strip runs @ 603whp it never made a hiccup! Just regular 30k fluid changes.
The guys so stand up, he redid my valvebody until it was just right. I'm not a fan of bouncing of the limiter & he redid it at least 4 times to get it just right for me. All at the cost of $2500 for a flat fee. This included shipping! I got a badass built trans that didn't jump the limiter, even at 600whp and met a very knowledgeable person in the process.
Moe @ SRT wanted quite a bit over $3000 to build my trans & that would include his "universal hardened" 3rd gear sprag & universal valvebody...and there wasn't a warranty if I went over 500whp. Haha he knew me all to well so I went with Jeff. Had Larry @ Sound Performance build my car made a max of 603whp. I sent Moe the dyno sheet & never looked back!
 
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I'm good on the valve body but I will be trying to contact him regarding the sprags for sure. Good lookin' out! Thank you casual!
 
AW4 Transmission Pan, PML Project Number 11076

PML has received a few requests from Jeep Cherokee and Wrangler owners for an aftermarket AW4 transmission pan. Not all Cherokee and Wranglers have this transmission. Some Toyota vehicles may have this transmission. It may also be known as the A340 transmission.

This project is on hold for several reasons. Vehicles lack clearance and exhaust and frame interfer with installation and fitment an aftermarket pan. The stock pan has a dipstick receiver, which makes designing and manufacturing a sand cast aluminum pan complicated and expensive. A pan with a bit more capacity would run at least $250 in the cast finish and a dipstick receiver would add about $80. To justify this project, we would need 50 people ready to buy and so far there have been seven requests. Thanks to Walter provided details on his stock pan.

If you have this transmission, let us know if you are interested. Email [email protected] or call (310) 671-4345.
 
AW4 Transmission Pan, PML Project Number 11076

PML has received a few requests from Jeep Cherokee and Wrangler owners for an aftermarket AW4 transmission pan. Not all Cherokee and Wranglers have this transmission. Some Toyota vehicles may have this transmission. It may also be known as the A340 transmission.

This project is on hold for several reasons. Vehicles lack clearance and exhaust and frame interfer with installation and fitment an aftermarket pan. The stock pan has a dipstick receiver, which makes designing and manufacturing a sand cast aluminum pan complicated and expensive. A pan with a bit more capacity would run at least $250 in the cast finish and a dipstick receiver would add about $80. To justify this project, we would need 50 people ready to buy and so far there have been seven requests. Thanks to Walter provided details on his stock pan.

If you have this transmission, let us know if you are interested. Email [email protected] or call (310) 671-4345.

How much MORE capacity would be added? I understand this project is in the early stages, but It was to my understanding certain 4runner pans were "larger in capacity" then the pan used in the Jeep Cherokee. I do believe this is a great idea, I just wonder if the cost is worth it?
 
what about a stamped steel pan similar to the stock design but deeper? still sounds like a rock magnet to me, i'd go with an external reservoir and a big cooler over a pan that hung lower if the extra capacity would make that much of a difference.
 
The tooling costs invloved for a stamping would be astronomical. We would need hundreds of pre-paid orders to justify the expense.

Here is what Marcus (Gojeep) did. A simple solution. Some street only pans have tubes running through the pan with the ends open to allow air flow. Increases cooling, but would be a mus trap for tose of us that run off the road... You can see examples of this idea on either Summit Racing or Jegs web site.

http://go.jeep-xj.info/HowtoAutoDeepPan.htm

I moved my Aux Transmission cooler out from in front of the radiator and onto the top of the front skid. Added a 6" puller fan to get the air moving along with a 185F thermoswitch to control the fan. My engine temps dropped a good 5F after removing the blockage the radiator.
 
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