signature600

You might check with www.transfercases.com...they might be able to build a 271 with a sensor location??

Just a thought!
Chris

HiJenks

I started reading this thread before Thanksgiving and was very interested in the swap as my tranny has 97K on it and is used 95% for towing.
My son just got his 2007 Chebby 2500HD with the allison and I got to see what the 6 spd with tow (manual) could do.
I'll be checking with you for more info !!!

Racing_Joe66

what do u mean difference in size on the adapters?? thickness or what?? i know someone that has one but he doesn't know how to tell either. so we are trying to figure it out.

thanks,
joe

gabe pm me back or call me.

Racing_Joe66

u say the flexplate is cummins and is solid. but a little before that u said "absolutely everything is changed. There is not a dodge part left from the flywheel housing back."

so if u change the flexplate then what cummins one do u use?? off a bus with a cummins motor and an allison trans?? or any aftermarket solid cummins flexplate will work as long as its solid??

thanks

Gabe32

the flexplate is a cummins and not a dodge. It is off a medium duty cummins with allison.

Racing_Joe66

any allison trans behind the cummins 6BT or more like a AT545 trans??

i know someone that has an adapter plate which is off of a Chevy - Grumman/Olson 17 foot stepvan, 1990, with a Cummins 4BT, which had a TH400 transmission. The adapter plate is to mount the TH400 behind the Cummins 4BT or 6BT engine, so it's a Cummins/GM
adapter plate.

would this adapter plate work?? also have the flexplate too. don't know if it would be the same for the allison. anyone know??

Gabe32

Won't work, different. AT545's had different variations of the housing. It is hard to tell if it would work or not. All that other stuff is different that your friend has.

Racing_Joe66

so would have to find a medium duty truck with an 1000 or 2000 series allison and the cummins to get an adapter?? and the flexplate off it too?? i found somewere though that the AT545 adapter was an SAE #3. or are there different SAE #3 adapters??

displacedtexan

Semi OT-

How hard would it be to bolt up an Atlas transfer case? That way you could have easy 2 low, and it should be more than strong enough.

LanceD

I am curious about this too. in fact, who knows what transfercases will mount behind the allison besides the GM 261?

displacedtexan

It seems like you can bolt the Atlas to the Ally, not a direct bolt up, but doesn't sound to bad either.

http://www.atlas-tc.com/download/SelectChart.pdf

Racing_Joe66

what kind of variations are there in the AT545----SAE #3 housing and an 1000-------SAE #3 housing?? will the starter and flexplate off an cummins to AT545 work??

LanceD

does the GM 261 have a PTO?

FDPOWER

there is an at 545, 645, 748. the flex plate off a 545 will not work. totally different

duratothemax

not to disagree with you because you are an "allison tech", but no it will NOT shift without J1939 data. That is NOT a standalone TCM, its a standard 3rd gen Allison TCM just like thousands of other trucks use. SO If its so standalone and only needs input speed, turbine speed, and output speed why the hell does he have like 50 wires running into it??? Yeah you can make the truck move without even having a TCM hooked up, but it will default to third gear and obviously not shift. The solenoids are set up to default to a certain N/O N/C fashion (if all power to the trans is cut) to allow the trans to limp home (in third gear) even if the TCM buys the farm or completely vaporizes for some reason. Beleive me I have tried LOTS of things with my trans and TCM and have somewhat of a good idea of how it works. If that DID work like you say it does, there would be hundreds of 12valve cummins's out there running LCT's. Just because the dedicated MIL-request wire is disconnected (no it doesnt do MIL requests thru J1939 like you say it does) do you think it wont throw any codes??? No, it doesnt care whether it tells you or not, if it wants to limp it WILL limp. Just for kicks I disconnected everything from my TCM except all the obvious PNP/NSBU wires and solenoid wires. Did I get a check engine light? NO. Did it shift and work normally? NO.

so I guess the TCM doesnt need any APP wires either?? Its THAT smart that It can vary shift points by using telepathic powers to know where your foot is??? Every automatic trans in the world has some sort of throttle pos sensor, whether is mechanical (TV) or electronic (APP). How would the trans know when to kick down? How would it know how much torque the engine is deleivering? How would it firm the shifts when you go WOT under full power? Youd slip the crap out if it IF it even shifted at all. You would probably even get a tie up because it has no idea what fill rates and apply pressures to use as far as controlling the trim solenoids and PCS.

guys you are welcome to try this on your mechanical 12valves, but you'll be wasting 600 bucks on a TCM that you cant use, and 3,000 bucks on an Allison trans that wont work.

ben