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Discussion Starter #1 (Edited)
After much deliberation, I have decided to stick with my aisin warner 4 speed auto in my Jeep. The question now comes down to a torque converter. So my question is, does anybody know of the aw4 ever being bolted up to a diesel of any shape form or fashion? A few things that might help is that this particular transmission was offered in various other manufacturers vehicles, namely volvo and toyota (both manufacturers of diesel powered vehicles). It also goes under a few different names such as A340 and #40-30-le. Any help would be greatly appreciated, as I have exhausted my knowledge resources and still haven't found an answer.

P.S. No offense but it would be appreciated if yall would limit your replies to the question at hand instead of "Why don't you shell out the money for xxxxx transmission or a custom torque converter" and "Are you sure that that will handle the torque?" My hands are somewhat tied at the moment. Thanx. York
 

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The AW-4 might just handle the power of the 4bt. I have tried to beat AW-4s into submission without luck, including towing 6,000+ lb. trailers (and not gently!) and just plain being dumb. If you aren't planning to use your XJ to tow with, it should handle the 4bt.

To answer your question...well, I can't. But I think the easiest route would be to send out your TC to have it rebuilt to your specs. Any decent rebuilder should be able to set it up to your desired stall speed, as well as welding on new tabs to match the flexplate of your choice.

That will deal with the transfer of power, but what about bolting up the transmission? Are you planning to fab your own adapter? You might be able to buy an adapter to go from Chrysler to Jeep from one of the popular adapter companies, then use the Dodge flywheel housing (or do the same with a GM FH).

You have one of the easiest years for controlling the AW-4, since you have a stand-alone controller already. I think all you really need is to mount up a TPS, either directly or by linkage.

Keep us updated. I have a couple XJs, and I would love for one of them to be a 4bt project if I can manage to get a garage to use again!

Jim
 

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Discussion Starter #3 (Edited)
That will deal with the transfer of power, but what about bolting up the transmission? Are you planning to fab your own adapter? You might be able to buy an adapter to go from Chrysler to Jeep from one of the popular adapter companies, then use the Dodge flywheel housing (or do the same with a GM FH).
As far as adapter plate I will probably fab up my own. I can't seem to find anybody that makes adapters for these things.
But I think the easiest route would be to send out your TC to have it rebuilt to your specs. Any decent rebuilder should be able to set it up to your desired stall speed, as well as welding on new tabs to match the flexplate of your choice.
How much do they usually charge to make custom torque converters?
You have one of the easiest years for controlling the AW-4, since you have a stand-alone controller already. I think all you really need is to mount up a TPS, either directly or by linkage.
Sweet, these were two of the other q's I was trying to get answers too. Just out of curiousity, what years had the stand alone controller, and is the tps the only input the tcm needs to shift automatically? How does the tps work? What about shift points? Also, have you seen these?: http://www.awshifting.com/controller.htm
This is what I was going to use if I couldn't figure anything better out. I may still get one, to get me on the road faster. Besides, I've always wanted one.:)

Great, now I'm straying off topic.:)
 

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I'm pretty sure ALL aw4's had a stand alone computer. I think it would hold up pretty well to the 4bt as well.

I would look into how the guys on here that mated an AX15 to the 4bt and how they did the adapter.

Not on exact topic either...good luck.

Related topic I think getting a custom converter is the absolute best way to go. Even stock diesel converts, i ran one with my 700r4, are too high of a stall for the 4bt. 1200-1400 rpm stall doesn't give the engine much range to rev up before it has to shift. i would have gotten a tighter converter if i'd kept the auto. I would guess 3-500 dollars for a mildly built custom converter.
 

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I have and a couple buddys have pounded on aw4's in our jeeps for years. They also seem to hold up fine to stroker 4.0L and supercharged. 275hp and 350 lbft.

only real drawback is what ya'll are already talking about with shifting, you can manually shift it by bypassing the computer with of those those kits mentioned. it would be real neat to figure out away to "keep it an auto"

I've always wanted to build a stroker out of my 4.0L in my comanche, but a 4bt would be even better.

keep up with the great ideas.
 

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Get a service manual (or find someone online who will scan a few pages for you) and trace the trans controller's wiring. The controller is up under the passenger side of the lower dash panel, under the glove box. Just a small rectangular metal box. And no, not all AW-4s used a stand alone controller, although I'm not sure which years did use them. I know the late 80's did, and I'm fairly sure up into the early to mid 90's. I'll try to get the info.

Jim
 

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How does that trans compare internally to others?

Dustin (AverageF250) has had several people try several different automatic transmissions behind the 4bt without success.
 

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Discussion Starter #8 (Edited)
I did some more searching and found that the aw4 had a stand alone controller from 87-98, and an integrated controller from 99-01.

What is a good stall speed for the 4bt? Also what rpm do yall usually shift at? My aw4 has 2.8:1(1st), 1.53:1(2nd),
1:1(3rd), .70:1(4th), and a lockup tc.
 

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Bobpr

Hi aw4's have been used in the Jackaroo diesel in Aussie I don't know the equivalent in the US, Toyota land cruisers, NPR Isuzu with 4HG1 engines,toyota dutro light truck, Mitsubishi & Mazda4000 trucks all around the 98 to 02 years they were not a very durable trans in isuzu who have now gone back to using the trans that was used prior to 98
 

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Durable

Hi aw4's have been used in the Jackaroo diesel in Aussie I don't know the equivalent in the US, Toyota land cruisers, NPR Isuzu with 4HG1 engines,toyota dutro light truck, Mitsubishi & Mazda4000 trucks all around the 98 to 02 years they were not a very durable trans in isuzu who have now gone back to using the trans that was used prior to 98
This may be true but the were considered bulletproof behind the 22R in Toyota 4-Runner. This is a lower power engine however
 

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This may be true but the were considered bulletproof behind the 22R in Toyota 4-Runner. This is a lower power engine however
The AW4 has proven itself to be very reliable behind the Jeep 4.0L inline 6 cylinder in the Cherokee. So much so that it is becoming a popular swap for replacing the Chrysler 42RE in the 4.0L ZJ Grand Cherokees. With that said, I wouldn't consider bolting an AW4 to a 4BT. It wasn't built to handle the torque delivery of the 4BT.

.
 

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Did anything ever come of this?

I'm sitting here with a dead 4.0 that has a good AW4 and I've not seen many/any XJ 4bt swaps.

Links to a newb would be appreciated!
 

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I'd love to wake this thread up as the AW4 is VERY available and cheap and strong and mates to many excellent transfer cases natively. This trans, in A340 Supra form, has taken a beating the likes of which few, if any, on this forum will ever dish out with a 4BT. The issue is heat generated through incorrectly matched stall and engine. I have read about users of the AW4 running tranny coolers even on stock applications. This has been heavily recommended from everywhere I read about this trans. It seems "bulletproof when kept cool" is something that is parroted.

I have issues with running the XJ controller in general. The AW4 has a pickup to deduce RPM itself. This is then passed on to a shift table designed for a 4.0L. It also requires throttle position as an external input. While not cheap, something like this should give the best result retaining full auto functionality:

http://www.powertraincontrolsolutions.com/transcontrol.php

Unlike when this thread was started, there are several Jeep(AMC) bell housing adapters on the market so I need not play favorites.

I have read of folks using a 24v throttle position rig on other cars. I like this idea as it doesn't require complex mechanical setup to get TPS.

The torque converter should be matched to the engine. A tighter one would generate less heat doing it's job. Heat kills automatics. Less heat, longer life and happier AW4. These guys do torque converters for this transmission. FYI they do not seem to respond to web requests. Might want to call them:

http://www.lextreme.com/tc.htm

That about wraps it up for the swap. I have amassed this info over quite some time. I hope you guys can make use of it. I have seen a couple 4BT AW4 swaps but none with a build up thread and none with any info. I am betting they either manually shift the AW4 or kept the stock controller. Both solutions I think will not give the best results. If you have a AW4 4BT with full auto functionality, send me any info you have in making this work.

I had an OM617 with an AW4 but that requires nothing as the OM617 generates little torque and has a usable RPM band VERY similar to the 4.0L. The stock converter and shift table work well. I also ran a complex mechanical rig to get TPS.
 

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If you were to use the AW4 I would seriously get on of those Aussie diesel AW4's. Most of the posts above mention the AW4 being a good trans behind any number of gas engines, only one post mentioned it being used with a diesel. The big difference between diesel applications and gas applications is the RPM range. The 4bt makes its torque very low in the RPM band and a gas engine trans can't holt that much torque that low there just isn't enough pump pressure yet. Not to mention the lack of a vacuum signal most gas engine autos use to modulate the shift points is not there on a forced induction engine.
I'm not trying to discourage the AW4 just point out some very important facts that have yet to be mentioned here, as well as some misconceptions between high RPM/ high horsepower gas engines and low RPM high torque diesels.
Adapters are out there, be creative in your search. What bolt pattern is your 4bt? lets say it is a GM then look for a toyota to SBC adapter, or a Dakota to SBC adapter these vehicles used versions of the Asain Warner trannies. I would stay away from Novak they HATE diesels and state they are not worth the time and effort. I tried their adapter and it was a huge PITA as well as the after sale customer support sucked.
 

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ive had the same experience with novak.

in terms of gas/diesel engines on the aw4, i believe a lower stall converter will make an aw4 work fine behind a diesel.
 

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The lower stall TC will not help the shifting or the pump output at lower RPM's. It is one piece of the puzzle but not enough all by itself.
 

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theres 3 solinoids that control the aw4 for shifting. two shift, one tc lockup. i dont mind running it as a quasi automatic, as the other option is scrapping it and going to a manual trans. i want to keep the aw4 for a few reasons.

I have an abundance of them, and a 4l80e runs about 1500 out of the gate, not to mention the cost of reconfiguring a tcase, etc. i dont mind throwing a new aw4 in every year worst case.
 
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