What sensors does it take for the Allison TCM to run by itself. I am assuming it takes a TPS. What else does the TCM require?
Allison Stand-A-Lone
- Thread starter duramaximizer
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So you are saying as long as the TCM sees those 4 things, it will run and operate as normal?
Just remember though that the stock ALLISON TCM's in a GM truck do not read an analog TPS, but it reads an APPS reading via the J1939 data bus. There are boxes out there that can send out this type of TPS signal, the most used one is the DESTROKED PCS box as it also can send out the tow/haul and OD/LO message as well.
5 speed. I am hoping to run a stock TCM and have everything be EFI Live tuneable and get to to shift without an ECM.
Not if it has the proper cal in it. He will need a MD cal that uses TPS inputs. Many MD cals are autodetect, which means the controller will look for inputs on both the TPS input and the J1939 bus. AFAIK GM cals are not autodetect and will not recognize TPS inputs on the analog input pin, but then again, I have never tried it.
Well, "harsh" is a relative term. MD cals are designed for trucks that are typically quite a bit heavier than a pickup. They will usually shift like a GM in tow/haul mode. Perhaps Mike can retune the shift tables to soften it up for you? AFAIK, EFILive will ONLY allow modification of GM OS'es - it won't tune other MD cals. I'm not 100% on this, so you probably will want to ask Ross or Paul about that. FWIW, MD GM apps (i.e. Kodiak, Top Kick) are tuneable with EFI Live but use digital throttle inputs, so choosing one of those isn't a solution.
I'm sure Mike or Ben will correct me if I'm wrong on this, but to my knowledge MD cals generally don't have multiple shift schedules (i.e., normal, tow/haul, 4WD low range) available. If you want those functions and/or you want to be EFI Live tuneable, you will probably have to run a GM OS and input your throttle digitally. Thats what I did with the 6 speed TCM to get all the goodies
I'm sure Mike or Ben will correct me if I'm wrong on this, but to my knowledge MD cals generally don't have multiple shift schedules (i.e., normal, tow/haul, 4WD low range) available. If you want those functions and/or you want to be EFI Live tuneable, you will probably have to run a GM OS and input your throttle digitally. Thats what I did with the 6 speed TCM to get all the goodies
ANY of the cal's for an ALLISON can have a secondary shift schedule enabled in them, tow/haul mode is just a proprietary term to GM. There are a few cals out ther that use an analog TPS for teh TCM input but not many. If this is going in something OTHER than a 1 ton truck or smaller, you can go to an ALLISON dealer and have the TCM custom tuned by them with there DOC software. They can locate a base OS and then customize the shift points and shift schedules for you to how you want them. I don't know what this will cost you though. And I believe EFILIVE can still access most all of the 1000/2000 series CAL's to make basic shift point and shift timing changes. What engine are you trying to mate this up to?
The trick is accessing a secondary shift schedule. I'm not sure how MD apps do it, but on GM apps the T/H input is sent to the BCM, which then sends the command over the low speed data line to the TCM to enable that shift schedule. The 4WD low shift schedule is simpler. There is a dedicated input on the TCM that you simply pull to ground to tell it you are in 4lo. I dont know if the MD cals recognize that input, since they are all 2WD.
According to the 3rd Gen 1000/2000/2400 Electronic Controls Troubleshooting Manual, The secondary shift schedule is activated with a switch across pins 10 & 28 on the grey connector (open circuit is primary, closed circuit is secondary). Disclaimer: I do not know if this applies to all cals, all MD cals, oe only certain cals, and take no responsibility if your TCM jumps out and sings Mary had a little lamb or explodes in a ball of fire .
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According to the 3rd Gen 1000/2000/2400 Electronic Controls Troubleshooting Manual, The secondary shift schedule is activated with a switch across pins 10 & 28 on the grey connector (open circuit is primary, closed circuit is secondary). Disclaimer: I do not know if this applies to all cals, all MD cals, oe only certain cals, and take no responsibility if your TCM jumps out and sings Mary had a little lamb or explodes in a ball of fire
Only works on the early models. It is T/H.
Oh, duh
..... That's on the Light Duty Cals, might still apply to MD cals as they may not have the same level of integration that the Pickup Cals have :dontknow:.But on the light duty, it's a momentary contact to toggle T/H. The Allison manual says it's a SPST switch that when open, primary schedule, when closed it's secondary.
You might try an 8.1 cal. I've heard (don't quote me on this) that the 8.1's TCM can get by with just a TPS input. :dontknow:
Is it going to be a carbed bbc or EFI? If EFI, what about starting with an 8.1's ECM & TCM, and tuning the ECM for the motor in question?
If anyone knows of a cal that might be in TIS2000 that woul dhave used a TPS, let me know. I know some GM MD VINs are in TIS2000. I was playing with some for the A40 TCM a while back.
Edit: See attached image; That's from the Allison 3rd Gen Controls manual I referenced eariler... I have NO clue if the input would actually work. SUPPOSEDLY some cals are auto sensing, and can detect what method of input is being used and configure for it on bootup.
Is it going to be a carbed bbc or EFI? If EFI, what about starting with an 8.1's ECM & TCM, and tuning the ECM for the motor in question?
If anyone knows of a cal that might be in TIS2000 that woul dhave used a TPS, let me know. I know some GM MD VINs are in TIS2000. I was playing with some for the A40 TCM a while back.
Edit: See attached image; That's from the Allison 3rd Gen Controls manual I referenced eariler... I have NO clue if the input would actually work. SUPPOSEDLY some cals are auto sensing, and can detect what method of input is being used and configure for it on bootup.
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