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The hard part is finding that rare and elusive MD mechanical engine trans calibration. The people that know which one to use won't talk or share for obvious reasons, as they stand to profit from it. I am going to use a 1000 series behind a 4-53 Detroit and most likely will have to have someone else flash the TCM with a MD calibration to get everything to work the way I want!!!

Mike
 

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Discussion Starter #702
DUD 45, regarding your question about all MD tcm's requiring a TPS input, some do and some dont..., the early ones connected to a mechanical injection engine require a tps input, latter ones with electronic control injection management dont recognize a tps signal. thats at least what i discovered when i did mine.
On a side note, my TCM is MD allison 5speed program, i was curious if a tap shift would work but was told by one of the tap shift kit manufacturer that it would not work as my tcm is not gm and the plugs and terminals are different.... i thought all 5 speed 3rd gen tcm's were physically the same and all terminal locations had the same function being gm or otherwise, the only difference is that some terminals are ...or are not used depending on program.
All gen 3 TCMs have the same connectors, and the main I/Os are on the same pins, but some of the secondary functions are different.
 

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I had ' cummins allison conversions " program mine, and i am not thrilled with it and they refuse to help me, saying that it is functioning correctly since it is not throwing error codes.
i had given them the application parameters, wheel sizes, axle ratios, vehicle weight, 14,000 to 16,000 lbs and it keeps on upshifting so i can find myself in 4th or 5th at 1200 rpm and 35mph or so.... it might work fine if the truck weights 6000lbs but sucks for me.
Apparently they only have ONE MD program with tps for the 2400 and really could not care less about the application. They just wanted my money and on top of it all, after sending my TCM to them, they charged me $25 shipping to send it out to be reflashed, $25 to get it shipped back to them and then $25 to ship it back to me. They send all the TCM's out to a dealer to have Allison programs loaded, they do NOTHING in house.... Im not sure why they say they are the experts.... i would of appreciated some honesty and simply be told that they dont have access to a program that would work for me as i had other options....
Anyways, i can manually downshift but Tap shift would be soooo much easier, and stepping on the pedal to make it down shifts works well but i find myself blacking out the horizon for a few seconds before it shifts... they dont seem to understand that 14,000 + lbs and 1200 RPM's in high gear simply doesnt work....
YEP... experts alright....
 

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I talked to them about some tuning and wasn't impressed at all. He had some super squirrel box for sale that he claimed solved everything.

I used Jason at Custom Vehicle Services.
http://customvehicleservices.com/

We were able to use the MD cal and EFI to tune the shift points and shift timing and a slue of other things that are way over my head. That being said we weren't the first ones to do that either. Dale, and a few others have used this setup with both the GM and MD cals with great success. Mine still needs a tweak here and there, but is very drivable even at WOT.
 

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The biggest thing is the ability to be able to tweak the programming to make it right for your application. Every combination is different and to say one size fits all ain't going to cut it. Contrary to popular belief, there isn't a whole lot Allison DOC is able to do to a transmission calibration. They can change a few strict parameters, and that is it. I came across this company http://www.transmissiontuner.com/. I haven't called them but from what they write up, they are very thorough. When I get closer I plan on giving them a call and pick their brain. Has anyone else here talked to them?? Just curious!

Mike
 

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^^^^^

Yeah that's Jason! Lol
So he is a stand up guy that actually knows what is going on, not just there to blow smoke up my ass and not help me after the sale???

Mike
 

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Discussion Starter #709
I thought about doing Allison TCM tuning for conversions, but I really don't like the idea of "tuning by spec". I like to be able to actually drive the vehicle with the owner and get it right the first time. I occasionally still think about getting back into it but I really don't have the time these days.
 

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Discussion Starter #711
That's the beauty of data logging. Being in the truck with data logging would be the best.
Data logging can't tell you how the shifts feel, unfortunately. But yeah, it would probably be adequate.
 

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Data logging can't tell you how the shifts feel, unfortunately. But yeah, it would probably be adequate.
Actually it can. It can show a flare or binding shift. I had a few when we were making changes and by data logging we were able to get the shifts perfect. Not to hard and not to soft like the GM factory tune.
 

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Good thread guys
I want an Allison 1000 behind my 12v Cummins 6bt thats in my Land Rover now...

I believe I am already SAE#3 bellhousing, hopefully I can find the flywheel and flexplate from a AT545 in the UK... just need to search for the ideal Allison... probably stateside as we dont have much smaller than 3000 series here...
 

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So guys, sorry for the double post but I have done some more digging and I have formed a more informed post... so here goes...

I am UK based and I want to hook a 6 speed Allison auto to my 12v Cummins 6BT in my Land Rover.

I have a 0-5v potentiometer from a 300tdi land rover that will fit on the VE pump of the Cummins to give the throttle input.

My Cummins is already an SAE3 bellhousing so the SAE3 style Allison with input speed sensor is ideal for me.

I want to close couple the land rover LT230 transfer box as close as I can to the rear of the Allison which will mean redesigning the rear output casting and the output shaft, loosing the rear speed sensor.
So I was hoping it would be possible to use the land rover transfer box speed sensor with the High / Low range correction for the 1.003:1 and 3.321:1 ranges?

I would also like the ability to shift up and down and drive it manually for off road driving.

So basically my question is what control method would you recommend?
Allison MD or Chevy?
I have a fairly friendly local Allison dealer who might be willing to custom map my shifts and lock up tables with the MD set up, I am waiting to hear back from them.

Also what torque converter would you recommend? I am aiming for a torquey 400hp set up on the Cummins for towing and economy which i know is on the limit for a 1000 Series Allison.

I look forward to your reply and any feedback you are willing to share.
 

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Discussion Starter #715
I want to close couple the land rover LT230 transfer box as close as I can to the rear of the Allison which will mean redesigning the rear output casting and the output shaft, loosing the rear speed sensor.
Get the 4WD rear housing used in Chevy and GMC 4WD pickups and the 4WD output shaft. You may have to source these parts from the US, but it will make adapting your t-case much easier. Before you use the LT230 case I would make sure it will handle the torque you will be pushing through it.

So I was hoping it would be possible to use the land rover transfer box speed sensor with the High / Low range correction for the 1.003:1 and 3.321:1 ranges?
If the speed sensor is variable reluctance (vs Hall effect) it should be no problem. Ideally a 40 tooth reluctor (aka tone wheel) would be best, but you can program pulses per kilometer so it isn't absolutely necessary. The Allison TCM can be programmed for different low range ratios; but only if using a TCM with a GM 4WD pickup truck OS. Likewise, tap-shift and Tow/haul mode will require a GM Pickup truck TCM.
 

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Get the 4WD rear housing used in Chevy and GMC 4WD pickups and the 4WD output shaft. You may have to source these parts from the US, but it will make adapting your t-case much easier. Before you use the LT230 case I would make sure it will handle the torque you will be pushing through it.
Thanks Max, do you have any pics of the rear housing? I was hoping to make a custom rear housing with the LT230 mounting built into it.
The rear tail shaft to the Allison is interchangeable isnt it? So could be replaced or modified to suit a standard LT230.

I have run the LT230 behind a 250hp-ish 12v Cummins 6BT in my Land Rover with 37" tyres for a while now, as have a few friends, and while we cannot find a specified rated input for the LT230 their construction and my previous experience makes me believe that it is more than strong enough for a Cummins Auto in a Land Rover whos gross train weight is 7,500kg.
The main cause of failure in the LT230 is overspeeding the centre diff through wheelspinning, the cross pins can now be up graded and simply locking the centre differential in low traction conditions removes the risk.

If the speed sensor is variable reluctance (vs Hall effect) it should be no problem. Ideally a 40 tooth reluctor (aka tone wheel) would be best, but you can program pulses per kilometer so it isn't absolutely necessary. The Allison TCM can be programmed for different low range ratios; but only if using a TCM with a GM 4WD pickup truck OS. Likewise, tap-shift and Tow/haul mode will require a GM Pickup truck TCM.
I will have to check the speed sensor used on the Td5 defenders but I think it is a Hall Effect type.
It seems that GM is the better way to go for the speed sensor correction and for the other features but as I will have my hands full rebuilding the Land Rover and mating the gearbox and transferbox I am looking for the easiest route when it comes to get the electronics talking and working properly.

Another question I have is, what would be the recommended torque converter for efficiency in such a light truck?
 

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Discussion Starter #717
Thanks Max, do you have any pics of the rear housing?






I was hoping to make a custom rear housing with the LT230 mounting built into it.
The rear tail shaft to the Allison is interchangeable isnt it? So could be replaced or modified to suit a standard LT230.
I'm not sure what you mean by "interchangeable". It is a separate part that can be modified, or have a new shaft built with the spline and length of your choice. The stock 4WD shaft is 29 spline 1.25M pitch, and it is the only 4WD shaft available. The pic below is a stock 29 spline shaft that I had resplined to 32 spline 24/48 pitch, which is the standard spline used in the GM TH400, 4L80E, 6L80E, late SM465, and GM NV4500.



I was able to do this because the minor diameter of the 29 tooth metric spline (1.350", approx. 34.3mm) is larger than the pitch centerline of the 32 tooth 24/48 spline. It is slightly smaller than the major diameter of the 32-24/48 spline, but the tooth contact is on the centerline so there was no strength loss or fitment issues. Whether you can make this work with the LT230 case depends on the pitch centerline diameter of it's input shaft. Otherwise, a fully custom shaft would be required. It's not a complicated part, but a complete one-off shaft will always cost more than a simple respline.

I have run the LT230 behind a 250hp-ish 12v Cummins 6BT in my Land Rover with 37" tyres for a while now, as have a few friends, and while we cannot find a specified rated input for the LT230 their construction and my previous experience makes me believe that it is more than strong enough for a Cummins Auto in a Land Rover whos gross train weight is 7,500kg.
The main cause of failure in the LT230 is overspeeding the centre diff through wheelspinning, the cross pins can now be up graded and simply locking the centre differential in low traction conditions removes the risk.
As is often the case we must go by experience and empirical evidence to determine what will work and what will not. It sounds as though your experience has determined it will work, so no worries there. Of course, an automatic generally puts less stress on the downstream components vs a manual.

I will have to check the speed sensor used on the Td5 defenders but I think it is a Hall Effect type.
Is the sensor 2 wire or 3 wire? 2 wire is variable reluctance while 3 wire is Hall effect. There may be exceptions to tha rule, but I'm not familiar with any. Then again, my experience with speed sensors on non-GM vehicles is limited. However, a Hall effect needs at least three conductors (power, ground, signal).

It seems that GM is the better way to go for the speed sensor correction and for the other features but as I will have my hands full rebuilding the Land Rover and mating the gearbox and transferbox I am looking for the easiest route when it comes to get the electronics talking and working properly.
Actually, the medium duty OS that uses an analog TPS is the simplest to get working, but it has no capability for correcting for 4WD low range ratio. As far as the GM OSes go, the 4WD 8.1L OS is the simplest to get working (you did read the whoel thread, right? ;) ). That limits you to 01-05 5 speeds and 06-10 6 speeds. 11-later GM pickup Allisons use a different valve body and only have OSes that work with DMax ECMs. Using any TCM with a DMax OS in it would require sending throttle inputs via GMLAN. This is a bummer with regard to the 11-later transmissions, because they have a variable pressure valve body that reduces parasitic hydraulic pump losses at idle, low speed, and cruise. My guess is that could be good for up to 1MPG improvement in fuel economy, but that's just a guess.

Another question I have is, what would be the recommended torque converter for efficiency in such a light truck?
Off the top of my head, I think the stock DMax converter was the TC-221 1.73 stall ratio unit, while the 8.1 used the TC-210 2.05 ratio unit (someone correct me if I remember incorrectly). Because the LR is so light, and because the Ally uses a lockuop converter, I think either would give equal fuel economy for normal street/highway driving, given the right calibration regarding when the converter locks. Off road at low speed, where the converter is running unlocked, tlighter is always better. The tightest OE converter is the TC-222, but I think it would be a bit of a slug. I'd probably stick with the DMax stall. Of course, aftermarket converters can be tuned for the stall and coupling you want (within reason, of course) and also give you better converter clutches. If you're going over 575lb-ft (780Nm) and/or 300HP(224kW) then you probably want a dual or triple disk converter, especially as a mechanical Cummins has no defuel capability. For that matter, you will want a Transgo SK Jr. kit as well. Those figures are Allison's limit for applications with no torque management (aka defuel).
 

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I'm not sure what you mean by "interchangeable". It is a separate part that can be modified, or have a new shaft built with the spline and length of your choice. The stock 4WD shaft is 29 spline 1.25M pitch, and it is the only 4WD shaft available. The pic below is a stock 29 spline shaft that I had resplined to 32 spline 24/48 pitch, which is the standard spline used in the GM TH400, 4L80E, 6L80E, late SM465, and GM NV4500.

I was able to do this because the minor diameter of the 29 tooth metric spline (1.350", approx. 34.3mm) is larger than the pitch centerline of the 32 tooth 24/48 spline. It is slightly smaller than the major diameter of the 32-24/48 spline, but the tooth contact is on the centerline so there was no strength loss or fitment issues. Whether you can make this work with the LT230 case depends on the pitch centerline diameter of it's input shaft. Otherwise, a fully custom shaft would be required. It's not a complicated part, but a complete one-off shaft will always cost more than a simple respline.

That is what I meant yes, looks like it would be possible to make a replacement suitable for the LT230 of if the shaft is solid then then it will probably be able to be skimmed down to LT230 input size.


As is often the case we must go by experience and empirical evidence to determine what will work and what will not. It sounds as though your experience has determined it will work, so no worries there. Of course, an automatic generally puts less stress on the downstream components vs a manual.
Yes hopefully so!

Is the sensor 2 wire or 3 wire? 2 wire is variable reluctance while 3 wire is Hall effect. There may be exceptions to tha rule, but I'm not familiar with any. Then again, my experience with speed sensors on non-GM vehicles is limited. However, a Hall effect needs at least three conductors (power, ground, signal).
I will have to do more research, the later LT230 with the electronic sensor also has a switch to tell the Td5 engine ECU it is in low range to alter throttle response, this could be used to automatically tell a speed sensor corrector to adjust for low range, I just have to work out how haha.


Actually, the medium duty OS that uses an analog TPS is the simplest to get working, but it has no capability for correcting for 4WD low range ratio. As far as the GM OSes go, the 4WD 8.1L OS is the simplest to get working (you did read the whoel thread, right? ;) ). That limits you to 01-05 5 speeds and 06-10 6 speeds. 11-later GM pickup Allisons use a different valve body and only have OSes that work with DMax ECMs. Using any TCM with a DMax OS in it would require sending throttle inputs via GMLAN. This is a bummer with regard to the 11-later transmissions, because they have a variable pressure valve body that reduces parasitic hydraulic pump losses at idle, low speed, and cruise. My guess is that could be good for up to 1MPG improvement in fuel economy, but that's just a guess.
Haha yes I spent a few hours reading and trying to digest the whole thread, but it was 2am so some may not have stuck lol
So in reality its 8.1 GM or MD Allison for earlier 6 speed boxes, 8.1 GM requiring more effort to tweak the TPS input and MD Allison requiring more effort to tweak the VSS input.

I have found this http://www.transmissiontuner.com/Allison-Swap.html
It looks like a simple drop in solution but I would like some feedback from those who have played with Allison transmissions or even used this set up? seems to shift well on the video of the telemetry.


Off the top of my head, I think the stock DMax converter was the TC-221 1.73 stall ratio unit, while the 8.1 used the TC-210 2.05 ratio unit (someone correct me if I remember incorrectly). Because the LR is so light, and because the Ally uses a lockuop converter, I think either would give equal fuel economy for normal street/highway driving, given the right calibration regarding when the converter locks. Off road at low speed, where the converter is running unlocked, tlighter is always better. The tightest OE converter is the TC-222, but I think it would be a bit of a slug. I'd probably stick with the DMax stall. Of course, aftermarket converters can be tuned for the stall and coupling you want (within reason, of course) and also give you better converter clutches. If you're going over 575lb-ft (780Nm) and/or 300HP(224kW) then you probably want a dual or triple disk converter, especially as a mechanical Cummins has no defuel capability. For that matter, you will want a Transgo SK Jr. kit as well. Those figures are Allison's limit for applications with no torque management (aka defuel).
Thanks, for relability it looks like I need the uprated torque converter and Transgo SK Jr, any recommendations as to which aftermarket converter to go for?

Thanks again for your assistance, its greatly appreciated!
 

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Discussion Starter #719
Thanks, for relability it looks like I need the uprated torque converter and Transgo SK Jr, any recommendations as to which aftermarket converter to go for?
Unfortunately I don't have any good recommendations. The problem with the Allison behind a Cummins is that all the performance Ally converters are designed for the Duramax, which has a different power curve vs a Cummins. Especially a mechanically injected Cummins. On top of that they are designed to be used in the stock 7000+lb Gm pickup, not a lighter vehicle.

That said, you may want to get hold of Suncoast, Goerend, or Precision Industries and see what they have to say. You may also want to look around for converter builders in your country.
 

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Unfortunately I don't have any good recommendations. The problem with the Allison behind a Cummins is that all the performance Ally converters are designed for the Duramax, which has a different power curve vs a Cummins. Especially a mechanically injected Cummins. On top of that they are designed to be used in the stock 7000+lb Gm pickup, not a lighter vehicle.

That said, you may want to get hold of Suncoast, Goerend, or Precision Industries and see what they have to say. You may also want to look around for converter builders in your country.
Ok thanks Max!
 
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