Building a diesel powered RHD TJ Wrangler (Picture Heavy)

[Wildman]

WOW, I'd thought you were on your way to finalizing your build. after your previous post. Other than time & money it doesn't sound too bad and as you said you have experience with the AW4. The PLUS also is that there is a lot of support out there for one.

But I also know how frustrating it can be when you are seeing that finish line but then have to take a detour. Good luck and hope this is the final round of mods you have to do.

 

[RustyAutoholicGuy]

WOW, I'd thought you were on your way to finalizing your build. after your previous post. Other than time & money it doesn't sound too bad and as you said you have experience with the AW4. The PLUS also is that there is a lot of support out there for one.

But I also know how frustrating it can be when you are seeing that finish line but then have to take a detour. Good luck and hope this is the final round of mods you have to do.

Thanks @Wildman. It's weird it's actually a relief to be moving away from the Ford 6r80 as it caused me to want to pull my hair out so many times. The great thing about the AW4 was it was very predictable in what it did both mechanically and when programming the tune with the CompuShift TCU as well.

Here's a great example. On my Quick6 controller right now I have a 3000rpm tune, meaning at 100% throttle, it will shift the transmission at 3000rpm regardless of my speed . . . I think (honestly I'm not even sure on that truthfully). It was very rarely that the controller would shift the transmission before 3000rpm, unless I all but pulled my foot off the throttle. I tried making a 4000rpm tune, as my TDI will easily rev to 4500rpm and I discovered that in practice that now meant EVERY shift happened at 4000rpm, unless again I pulled my foot completely off the throttle. I've been fighting that issues for months now. With the CompuShift I never had that problem, shifting was always proportional to throttle input. Now to be fair this could caused by the mismatched torque converter but I don't have a good way of verifying that either.

Another thing that I found annoying with the Quick6 was their Shiftware software to tune the controller. Supposedly it would work with any version of Windows, but I never could get their Software to communicate with the Quick6 unless I was running Windows 95. So I would run a VM of Windows 95 on my Macbook Air just so I could tune the controller. On the CompuShift I can program the controller from my iPhone or Android phone along with both Windows and Mac laptops of Bluetooth. The Quick6 is over USB only.

And yet another thing was how the Shiftware interface would change based on the tune you loaded. Now I have to give credit to USShift, when you download Shiftware, you get a TON of base tunes for various RPMs and applications. But what drove me crazy was based on the tune you loaded, the tables and values you could interact with changed. They have, soft, street and firm tunes, but I have no idea what or how it changes the tables in the software. Along with that the documentation on what it does is basically none existent as well.

This is where I feel CompuShift really shined. Everything was well laid out in their software and if you had questions their manuals were very detailed on what each feature did as well. Now you can't really compare the two as I'm comparing a 4-speed automatic to a 6-speed automatic. The two transmission are VASTLY different. However having emailed both companies and talked to them on the phone as well, I was always able to get more support from CompuShift than USShift.

So yes it's more work and fabricating to be done but in a way less stress knowing I'm going not only to a transmission that I know works but also going to a TCU that I know how to tune as well.

-Grant

 

[Wildman]

Just having the options to swap drivetrain like you are is great. As we've discussed before IMO it'd be nice to have some of these options available with my swap. Of course, I haven't searched extensively but as far as I know there really aren't any quick easy swaps for the transmission.
I "THINK" it'd be nice to have those extra gears in the transmission.

 

[RustyAutoholicGuy]

Just having the options to swap drivetrain like you are is great. As we've discussed before IMO it'd be nice to have some of these options available with my swap. Of course, I haven't searched extensively but as far as I know there really aren't any quick easy swaps for the transmission.
I "THINK" it'd be nice to have those extra gears in the transmission.

Yeah I know what you mean, in many ways swapping just the engine is SO much easier. I've already decided to keep my driveshafts, adapter, transmission and crossmember for the 6r80 so if and when another company comes out with a controller for the 6r80, I want to be able to bolt everything back into place and see how it does. Theoretically I should be able to switch everything back in a weekend that way.

I actually considered going to an AX-15 to just be done with it. I actually got a set of Manual Transmission pedals for a Right Hand Drive TJ Wrangler in from Australia as a last resort back up plan.

But I'm still bound and determined to have an automatic. The other nice thing about the CompuShift that I forgot to mention is it can get all the information it needs from the CANBUS on my TDI ECU. So to wire the controller up will only be 4 wires. Ground, Key Switch Power and the two CANBUS wires.

-Grant

 

[BugoutJeep]

Yeah I know what you mean, in many ways swapping just the engine is SO much easier. I've already decided to keep my driveshafts, adapter, transmission and crossmember for the 6r80 so if and when another company comes out with a controller for the 6r80, I want to be able to bolt everything back into place and see how it does. Theoretically I should be able to switch everything back in a weekend that way.

I actually considered going to an AX-15 to just be done with it. I actually got a set of Manual Transmission pedals for a Right Hand Drive TJ Wrangler in from Australia as a last resort back up plan.

View attachment 363863

But I'm still bound and determined to have an automatic. The other nice thing about the CompuShift that I forgot to mention is it can get all the information it needs from the CANBUS on my TDI ECU. So to wire the controller up will only be 4 wires. Ground, Key Switch Power and the two CANBUS wires.

-Grant

My AX-15 is starting to get really noisy and I think it's on its way out. I know so little about automatics and it's interesting reading your thread, because if I go with an auto then there's a lot of stuff I have to figure out too and you seem to be having troubles, that I'm going to face if I go to an Auto. Of course having the TJ with such a short wheelbase, I'm a bit more limited in options. I've been thinking about increasing the wheelbase, but it's just a bigger project than I want to tackle right now.

I've been waiting for the AX-15 to bite the dust, but I was hoping it would take a bit longer, since I've been undecided on what to replace it with. However I've been wanting to get it tuned and the 400 ft-lbs tune is very interesting IMO and it limits some transmission options as well. I've been thinking about 1 of these 6 speed autos, but I just know so little about getting them to shift right, how to get it to work with the R2.8, what Tcases will work, cooling issues, torque converter, etc.

I'm kind of just thinking of going with the TR-4050 and though a very big transmission (and expensive, since I think I have to buy them new), at least it's a fairly known quantity. And my wife and I can both drive manuals, though she really doesn't prefer them and I've been really hesitant to let her drive the Jeep with the R2.8 because she is always heavy on the throttle and I knew my AX-15 was old when I started the build and didn't want to break it for awhile.

In any case reading your struggles is kind of scaring me away from an Auto, especially since I either want a 6 speed Auto with granny gear and 2 ODs or a manual transmission with a granny gear and OD. Are you able to manually shift the auto? I've always known I don't think I could get 1 of these to ever shift just right and thought maybe I could just manually shift it. Heck I don't like how OEM autos shift, so I'm picky, but it's just that I'm used to always picking gears.

 

[Irun]

I'm getting dizzy trying to keep up Grant! Did I get this correct? You're moving to a AW4, based on the operating range of 3000 - 3500 RPMs. This will then simplify the controller wiring, using the CompuShift, to four wires.

 

[Noslo65]

Did you look into CotyBuilt or what they have to offer? I believe they sell an interface to utilize the original gauges.

 

[RustyAutoholicGuy]

My AX-15 is starting to get really noisy and I think it's on its way out. I know so little about automatics and it's interesting reading your thread, because if I go with an auto then there's a lot of stuff I have to figure out too and you seem to be having troubles, that I'm going to face if I go to an Auto. Of course having the TJ with such a short wheelbase, I'm a bit more limited in options. I've been thinking about increasing the wheelbase, but it's just a bigger project than I want to tackle right now.

I've been waiting for the AX-15 to bite the dust, but I was hoping it would take a bit longer, since I've been undecided on what to replace it with. However I've been wanting to get it tuned and the 400 ft-lbs tune is very interesting IMO and it limits some transmission options as well. I've been thinking about 1 of these 6 speed autos, but I just know so little about getting them to shift right, how to get it to work with the R2.8, what Tcases will work, cooling issues, torque converter, etc.

I'm kind of just thinking of going with the TR-4050 and though a very big transmission (and expensive, since I think I have to buy them new), at least it's a fairly known quantity. And my wife and I can both drive manuals, though she really doesn't prefer them and I've been really hesitant to let her drive the Jeep with the R2.8 because she is always heavy on the throttle and I knew my AX-15 was old when I started the build and didn't want to break it for awhile.

In any case reading your struggles is kind of scaring me away from an AI uto, especially since I either want a 6 speed Auto with granny gear and 2 ODs or a manual transmission with a granny gear and OD. Are you able to manually shift the auto? I've always known I don't think I could get 1 of these to ever shift just right and thought maybe I could just manually shift it. Heck I don't like how OEM autos shift, so I'm picky, but it's just that I'm used to always picking gears.

So I believe you have the Cummins R2.8 and people have done the Cummins to the 6r80 before so there is help out there not only for the tune, but also the torque converter specs as well which I feel like is huge! I believe QuickDraw is the company that makes that adapter.

As for the question on manual shifting. Yes I can I manual shift both the Quick6 for 6r80 and the CompuShift for AW4. You can actually do some neat things like engage torque lock up when in manual mode, I believe they call it an offroad mode, so it behaves like a manual transmission. The manual mode is great, I've really enjoyed it both on and off the road when I don't have the tune just right.

I think the 6r80 would work well with your R2.8, if only because it's been done before. It also helps that your R2.8 is putting out similar power the modular Ford V8 as well. Make sure to get a 6r80 from a 2014 or newer Ford. In all my research I learned that they did a refresh on the transmission to fix several of the issues with it.

I'm getting dizzy trying to keep up Grant! Did I get this correct? You're moving to a AW4, based on the operating range of 3000 - 3500 RPMs. This will then simplify the controller wiring, using the CompuShift, to four wires.

I worded that poorly, what I was trying to say is I'm not going to have the issues I had with AW4 and the Kubota because of the Kubota's limited operating range. The AW4 is a better match for my TDI in terms of power output compared to the 6r80 meaning my TDI and the 4.0l make similar power. With the Ford 6r80 I made way LESS power than the modular V8, which was causing my torque converter to be way off which hasn't been helping my issues.

Yes going to the AW4 will simplify so many things and the CompuShift is a great controller for it, much easier to tune as well. The other thing I have learned this weekend about the CompuShift is that it can communicate via CANBUS with my TDI ECU, so it will get RPM, TPS, and bunch of other data over CANBUS. What's neat about that as well is in talking with the guys at CompuShift, they have mapped out the TDI ECU so that can do torque vectoring on the engine during shifts to soften the shift and they can do other neat things as well since they will be able to see how much boost the engine is making as well.

I think it will be 4 wires minimum, ground, key switched power and the two CANBUS wires, but I'll probably have a few more wires for my shifter for manual mode and for the switch on the transfer case so the controller knows when I'm 4Lo as well.

Did you look into CotyBuilt or what they have to offer? I believe they sell an interface to utilize the original gauges.

I did a long time ago and ruled it out at the time. Their kit only works for manual transmissions and you can't decided where you want to mount the engine either. Because my Jeep was automatic, their interface wasn't going to work either, at least this was the case back in 2018 when I was researching all of this, that could have easily changed in the last few years.

 

[Wildman]

Not trying to add to your list of stuff but are you aware of Radesigns Products?
http://www.radesignsproducts.com/products-1.html

They make some pretty cool stuff for the AW4 along with other transmissions.

 

[RustyAutoholicGuy]

Not trying to add to your list of stuff but are you aware of Radesigns Products?
http://www.radesignsproducts.com/products-1.html

They make some pretty cool stuff for the AW4 along with other transmissions.

I actually have this AW4 kit for a Winter Carr Shifter in my shop still, I need to figure out how to install it. I actually forgot about it until you just posted about it honestly. I'm going to try to keep my current shifter, I really like the way it works, but if I can't, I'll be going back that shifter.

 

[BugoutJeep]

So I believe you have the Cummins R2.8 and people have done the Cummins to the 6r80 before so there is help out there not only for the tune, but also the torque converter specs as well which I feel like is huge! I believe QuickDraw is the company that makes that adapter.

As for the question on manual shifting. Yes I can I manual shift both the Quick6 for 6r80 and the CompuShift for AW4. You can actually do some neat things like engage torque lock up when in manual mode, I believe they call it an offroad mode, so it behaves like a manual transmission. The manual mode is great, I've really enjoyed it both on and off the road when I don't have the tune just right.

I think the 6r80 would work well with your R2.8, if only because it's been done before. It also helps that your R2.8 is putting out similar power the modular Ford V8 as well. Make sure to get a 6r80 from a 2014 or newer Ford. In all my research I learned that they did a refresh on the transmission to fix several of the issues with it.

How long is the 6R80?

I see the 6L80 used a lot more in R2.8 builds. I actually remember and I'd talked with Steve from Cummins (I think he's their marketing director) and he said he still has issues with his 6L80E and barely got it to fit in his 100" wheelbase build and he had some options he doesn't have to pay for. I'm on another R2.8 Cummins forum and there's always questions that people are having trouble with the R2.8 Cummins and transmission talking to each other.

There is a different low profile rear cover I can get for the R2.8 to save some additional room and I can get different bellhousings for the transmissions to R2.8 engine and currently my Cummins is ~1.5 to 2" forward of the 4.0L. Looks like I can get a SYE that's ~3" shorter than OEM, though I'm not sure which Tcase for those 6 speed autos. Though I love the Atlas tcases, I just don't want to drop $2,500 on top of the transmission, adapters, driveshafts, engine tune, shift tuner, etc.

If I go with the TR-4050, I'll be in it, SYE, driveshaft(s) for around $6k and everything is brand new. I'm not sure what the autos will end up running, but I'm curious if it's actually a deal or not coming from junk yards and my local yard isn't cheap so I typically just order stuff, which is even more expensive.

 

[Wildman]

The 6R80 is 23.75" long which is slightly longer than a AX15.

https://wranglertjforum.com/threads/jezzas-ford-6r80-transmission-swap.64366/#post-1178590

This thread might help answer some questions.

 

[BugoutJeep]

Sorry for the derail.

This transmission looks perfect on paper.... but it does seem tricky to get right. And like so often, if you start off in used, unknown condition and you have issues, it'll be incredibly hard to determine what the problem is, especially with the programing and computer stuff required. Not sure if it's the same issue, but last year I knew people that had to wait months to get various controllers that had gone bad on their vehicles.

At the moment I'm leaning back towards the TR-4050 brand new, but I don't have time to work on this for months, so maybe if someone figures this stuff out I'll look at Autos. Even with some pretty experienced builders, I hear of issues with automatics. One of the guys at work was trying to get his Mustang dialed in and it just isn't ever right. And not only is pulling a transmission annoying, but it seems like there's always something to buy each time that runs somewhere around $1k. I'm starting to think the $6k to get the TR-4050 installed isn't sounding as bad as I'd originally thought, though it's not perfect either and I still have questions about fitment on it.

 

[RustyAutoholicGuy]

Sorry for the derail.

This transmission looks perfect on paper.... but it does seem tricky to get right. And like so often, if you start off in used, unknown condition and you have issues, it'll be incredibly hard to determine what the problem is, especially with the programing and computer stuff required. Not sure if it's the same issue, but last year I knew people that had to wait months to get various controllers that had gone bad on their vehicles.

At the moment I'm leaning back towards the TR-4050 brand new, but I don't have time to work on this for months, so maybe if someone figures this stuff out I'll look at Autos. Even with some pretty experienced builders, I hear of issues with automatics. One of the guys at work was trying to get his Mustang dialed in and it just isn't ever right. And not only is pulling a transmission annoying, but it seems like there's always something to buy each time that runs somewhere around $1k. I'm starting to think the $6k to get the TR-4050 installed isn't sounding as bad as I'd originally thought, though it's not perfect either and I still have questions about fitment on it.

My other issue with the 6r80 controller, the Quick6 is that I feel they are trying to do too many things to few inputs. When I first did my research on the 6r80 I was really impressed with the Quick6 controller for how few things you had to wire up to the controller. Power, Ground, TPS and RPM. I really thought that would the ticket to getting my build down.

Now 18 months later, I realize just how much information a transmission needs to operate correctly. In talking with the folks at CompuShift, I'm going to be using the CANBUS system which is actually a two way communication, not just a one-way monitoring of the engine ECU. What's impressed me with the CompuShift unit is they use multiple data points to determine shifting. Even looking back when I first used the CompuShift unit I had to supply it RPM, Throttle Position and MAP as well so it could shift accurately when I was running the Kubota V2403.

With TDI ECU they are going to be able to determine shifting on all the information the engine has, for example delaying shifting when the engine is cold so it can warm up faster but also send the ECU commands so that it reduces the torque output of the TDI engine so soften the shift on the AW4 automatic to extend the life of the clutches in the transmission.

All of this is to say, if I wasn't so dead set on an automatic, a manual transmission would make finishing this build almost instantaneous. I've looked into the TR-4050 before, I really like the first and reverse gears being something like 6:1 right? I believe you could drive it on the street though with just 2nd ~ 5th gear as well. It's expense but seems like a fairly stout transmission as well.

 

[RustyAutoholicGuy]

Hey TJers,

While the AW4 is known to have some heat issues, if properly maintained and properly cooled it's actually a fairly stout transmission. I never had any issues with my first AW4 with the gobs of low end torque my Kubota V2403 turbo diesel threw at the transmission. The problem I have with AW4 on my BEW TDI diesel swap is the fact that my engine is drive by wire not drive by cable. The AW4 has what is called a TV Cable, Throttle Valve, that controls line pressure inside the valve body of the transmission.

Thanks to a suggestion from the people at HGM Electronics who make the CompuShift controller I will be using, I acquired a 2007 Toyota Tacoma A340F to see if I could build a hybrid transmission for my build. I'm not sure how it happens but I'm yet again embarking on a unique build for my TDI swapped TJ Wrangler.

Everything I'm trying to accomplished is only possible because of the CompuShift TCU that I'll be running in my TJ Wrangler. I had contacted HGM Electronics about using their CompuShift controller that I already owned from my first attempt at diesel swapping this Wrangler. I think this is attempt 4 or 5, at this point I've lost count.

I contacted HGM Electronics because I was re-reading their documentation on the controller and how it could communicate via CANBUS and I was curious if that CANBUS communication could be used to supply the inputs required for the CompuShift controller to shift the AW4 correctly. In talking with them, they asked how I was going to handle the TV Cable with my drive by wire diesel engine which lead me down the rabbit hole of what I'm now building.

As of now this transmission is completely untested but in theory and by all appearances should work. The Jeep AW4 and the Toyota A340F are both from the same family of transmission built by Aisin Warner called an A340. Basically this A340 transmission has used in vehicles from the 1980s until the the early 2010s before high gear count automatics started to become more common place. Aisin Warner throughout the years just kept improving this transmission.

To my surprise the valve body from the 2007 Toyota Tacoma A340F fit perfectly into the case of my AW4 out of a 1995 Jeep Cherokee. The other parts I used were the transmission pan and a temperature sensor from the A340F that bolted onto my Jeep's AW4 case without any modifications.

I didn't address this in my video but figured I would here. In reality I could easily just have gotten a Toyota TDI adapter and ran a Toyota transmission in my TJ Wrangler. I went with the AW4 transmission because I wanted to run a Jeep transfer case. The second reason for all of this is this transmission doesn't work with my setup, I'm going to finally abandon my pursuit of a automatic diesel powered TJ and just go with either an AX-15, NV2550 or NSG370 manual transmission in my Right Hand Drive TJ to finally have this project done. I guess only time will tell on all of this.

Here is the video if you'd like to watch:

Thanks
Grant

 

[Wildman]

WOW, you are a true glutton for punishment, not that I have any room to talk here but I'm watching just out of curiosity. I know on the 44/46RE if the TV cable isn't properly adjusted it'll cause shifting issues and if not hooked up, you'll smoke the transmission. So good luck and I really do think you should keep at the diesel/auto TJ project. I know you want it finished but I do think you'll be disappointed if you go with a manual.

 

[RustyAutoholicGuy]

WOW, you are a true glutton for punishment, not that I have any room to talk here but I'm watching just out of curiosity. I know on the 44/46RE if the TV cable isn't properly adjusted it'll cause shifting issues and if not hooked up, you'll smoke the transmission. So good luck and I really do think you should keep at the diesel/auto TJ project. I know you want it finished but I do think you'll be disappointed if you go with a manual.

Honestly I agree with you @Wildman about keeping this TJ automatic. If for whatever reason this doesn't work, I've decided to take a hard look at a th350 with a reverse manual valve body and at that point I'll probably go with a Dana 300 with one of those new aluminum cases for my transfer case.

 

[Wildman]

Honestly I agree with you @Wildman about keeping this TJ automatic. If for whatever reason this doesn't work, I've decided to take a hard look at a th350 with a reverse manual valve body and at that point I'll probably go with a Dana 300 with one of those new aluminum cases for my transfer case.

I was wondering if there isn't a way to have something to emulate the throttle action to move the TV cable? If this doesn't work out that is.

 

[RustyAutoholicGuy]

I was wondering if there isn't a way to have something to emulate the throttle action to move the TV cable? If this doesn't work out that is.

For the AW4 I don't believe there is, it needs a computer of some kind to operate. It's why if this doesn't work I'm going to go the TH350 route with a reverse manual valve body and probably a doubler to Dana 300 setup. My gearing I have in my axles now will work great for a 3-speed automatic but I can't really use 4th gear.

If I can confirm this setup works and everything talks to each other like it should and the transmission and engine work like they should, I'll be regearing my TJ. I'm just not sure what the gearing is going to be. Debating either 4.56 or 4.88. If I ever want to go to a bigger tire then just going to a 4.88 gear set is probably what I should go with. I can see a lift and 33" tires in this Jeeps future at some point.

 

[Rickyd]

The tdi may be dbw but you still have a gas pedal with physical motion.

To me it seems simple to find out what the range of motion the aw4 cable uses and attach some kind of lever to the throttle pedal arm with the appropriate length to get your correct throw?