T87 Swaps
- Thread starter kidturbo
- Start date
Thanks much. Don't know why I was thinking there was an 8spd version tucked in there then... So both the T87 and T87A use 6spd code. That's helpful.
Now who has HP Tunners software and can compare the two versions for me? Everyone seems to prefer the T87A over the T87 because it has a better 64bit processor. But since I'm moving faster at reverse engineering these units than EFIlive is at releasing any new tuning options, I could sure use hand reviewing the OS differences. I know there is a lot of tricks that can be done with the 87A. It even has Fuzzy gears options...
" Enables the calculation of a fuzzy downshift gear in a variety of modes or disables the calculation. Each mode can be individually enabled/disabled. "
I thought these TCMs already used what we would consider fuzzy logic for gear shifting. They already use throttle, RPM, and MPH to calculate the shifts. Unless they add an accelerometer to these vehicles I don't think there is anything that they can do to the "logic" to make it much better. And the vehicle speed sensor already gives it 90% of that information anyways
IMO, EFIlive didn't spend much time mapping out the T87 Allison tables. Compared to the gasser T87, which is quite detailed in EFI, this one barely has any tables to modify. And as mentioned above, no ability to turn off pesky DTC's.
What it also lacks is the majority of PID's for logging relevant transmission data. While not something EFI could even add to this OS tune, because Allison didn't include them origionally, I'll bet the 87A has them. IE: The 2016 E92 T87 gasser version gives you PIDs for logging Engine RPM, Engine ECT, IAT, all of your requested modes, and the current gear position requested, along with shift status and more. None of which I see available in this T87 Allison version. After running the gasser version on bench, I had to do a PID verification command just to clean up the options and determine what is actually available.
But I'll bet many those missing PID's are in the T87A. Guessing this based off the amount of canbus data I see the early L5P sending to the TCM, vs an LML or our LMM per say. Plus I have the A2l, which allows ya to simply add a CAX file to EFI tune software, and voila, you have the ability to modify any tables the coders factory OS included. Like changing a max RPM in table values, disable a DTC, or maybe write out everything related to a missing pressure control solenoid...
While we might not be able to modify this T87 firmware yet, I still plan to make it talk to the earlier ECM's as planned. It's cheap, unlocked, and readily available in bone yards. So long as no hard coded conflicts arise that would mandate a custom CAX or special bin file are needed. I do know that ATS is modifying the T87A bin file on units they supply for some reason. Am sure I'll find it soon enough.
For the short term I say we remain focused on the actually hardware differences that MUST be overcome with either unit. Starting with these speed sensors. She ain't ever gonna leave limp mode with either TCM unless these little pickups are working correctly.
@Cougar281 said he would like to see the option to change physical sensors in this design. Which is good idea, if we can source them.. I plan to resolve the issue on the PCB doing the canbus conversions, but can add a bypass switch so one or both can be updated in the transmission itself. While I test this conversion option, here is a couple videos on the differences.. One thing to keep in mind, the T87 Allison's uses the more rare 2-Wire Hall Effect versions.
Source: https://youtu.be/lTAW0lTqP6s?si=q--NUiCJxrY2ESDl
More detailed comparison with cooler graphics..
Source: https://youtu.be/MEpZRcPZGxM?si=pemAo5eEkiKh4oMT
What it also lacks is the majority of PID's for logging relevant transmission data. While not something EFI could even add to this OS tune, because Allison didn't include them origionally, I'll bet the 87A has them. IE: The 2016 E92 T87 gasser version gives you PIDs for logging Engine RPM, Engine ECT, IAT, all of your requested modes, and the current gear position requested, along with shift status and more. None of which I see available in this T87 Allison version. After running the gasser version on bench, I had to do a PID verification command just to clean up the options and determine what is actually available.
But I'll bet many those missing PID's are in the T87A. Guessing this based off the amount of canbus data I see the early L5P sending to the TCM, vs an LML or our LMM per say. Plus I have the A2l, which allows ya to simply add a CAX file to EFI tune software, and voila, you have the ability to modify any tables the coders factory OS included. Like changing a max RPM in table values, disable a DTC, or maybe write out everything related to a missing pressure control solenoid...
While we might not be able to modify this T87 firmware yet, I still plan to make it talk to the earlier ECM's as planned. It's cheap, unlocked, and readily available in bone yards. So long as no hard coded conflicts arise that would mandate a custom CAX or special bin file are needed. I do know that ATS is modifying the T87A bin file on units they supply for some reason. Am sure I'll find it soon enough.
For the short term I say we remain focused on the actually hardware differences that MUST be overcome with either unit. Starting with these speed sensors. She ain't ever gonna leave limp mode with either TCM unless these little pickups are working correctly.
@Cougar281 said he would like to see the option to change physical sensors in this design. Which is good idea, if we can source them.. I plan to resolve the issue on the PCB doing the canbus conversions, but can add a bypass switch so one or both can be updated in the transmission itself. While I test this conversion option, here is a couple videos on the differences.. One thing to keep in mind, the T87 Allison's uses the more rare 2-Wire Hall Effect versions.
More detailed comparison with cooler graphics..
So the DTCs not being there to modify in EFILive I Think is a combination EFILive/Allison thing - if you go look at A40 tunes from 2006, there is not 'Transmission Diagnostics' segment populated, but if you open one from a 2006 Express, which had a T42 and I think a 4L80E (The tune claims it's a 4T80E, but last I looked, they didn't stuff the 6.6 Duramax sideways in the express van 
), the 'Transmission Diagnostics' is quite fleshed out.
), the 'Transmission Diagnostics' is quite fleshed out.
Yes, I believe so also on the dtc map. Kinda why I was hoping that someone with hpt could review what their software has to offer.
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So based on the only Allison HPT file I could find (An A40 file), it seems like they have the same issue with the Allison calibrations and diagnostics... That is also blank with them... but man... 1997 called and wants their UI back!
I know, it's hard to find good shareware these days. 
Wonder if ChatGPT could build us a cool UI to incorporate all the giod bin editing and flashing tools that exist out there in the ether? Ah wait, it has a 90's IRC interface..
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Wonder if ChatGPT could build us a cool UI to incorporate all the giod bin editing and flashing tools that exist out there in the ether? Ah wait, it has a 90's IRC interface..
Sent from my SM-S901U using Tapatalk
What y'all think about this idea?
Feature
Upgraded
Transmission
Control
Module
Sent from my SM-S901U using Tapatalk
Feature
Upgraded
Transmission
Control
Module
Sent from my SM-S901U using Tapatalk
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What would you like compared with HP?Thanks much. Don't know why I was thinking there was an 8spd version tucked in there then... So both the T87 and T87A use 6spd code. That's helpful.
Now who has HP Tunners software and can compare the two versions for me? Everyone seems to prefer the T87A over the T87 because it has a better 64bit processor. But since I'm moving faster at reverse engineering these units than EFIlive is at releasing any new tuning options, I could sure use hand reviewing the OS differences. I know there is a lot of tricks that can be done with the 87A. It even has Fuzzy gears options...
" Enables the calculation of a fuzzy downshift gear in a variety of modes or disables the calculation. Each mode can be individually enabled/disabled. "
HP has DTC list for Allison t87a…
The speed sensors physically can be swapped in the Allison housing aswell.
I can send you a t87a HPtuners file if you would like. Email addy?
Thanks for the info, an 87 comparison would be great. Will PM ya.
The biggest thing right off is the DTCs. While I've been told you can just max the pressure table for the control valve and it's happy, that too isn't an option I see in the 2015 EFI version.
I spent a couple of hours today searching for a 2015 truck locally to capture some live canbus data.. Think I found every year, but the one with updated mirrors...
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So the biggest problem here is the AI component could inject random code to where you're driving at 85 in an 80, it commands a shift that'll result in a a tie up, locking everything up, causing a 98 car pileup with 52 dead.... HAs nobody seen The Terminator, Moonfall, The Matrix, I, Robot, etc..?Anything can be science fiction.... until it's not... How much do we have today that was science fiction 125 years ago? Sorry for the slight derail lol....What y'all think about this idea?
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I was actually talking about the A50 case with T87 stuffed in it... Take your broke A$$ T14, cut it open, stuff a bone yard T87 inside, add a little black duct tape, we got a fix. All from recycled parts.
Actually subbed out the connector fab job today, and was planning to go with a harness that allows moving the TCM away from stock location. Then realized, there is really nowhere else to stick it. So now I''m thinking we 3d print a new case from good material, keep the mounts, and maybe, just maybe, peal the T87 PCB out of it's case and rehome it. Gotta sneak another small board into the mix, and why not just stack it all together in the same A50 footprint? Unless someone has a better spot to stick it ?
AI can't even spell Ya'll correctly.. So I sure the heck ain't letting it drive me around town yet. That would be to freaking weird... LOL But the name FUTCM, might actually fit if ya did..
Actually subbed out the connector fab job today, and was planning to go with a harness that allows moving the TCM away from stock location. Then realized, there is really nowhere else to stick it. So now I''m thinking we 3d print a new case from good material, keep the mounts, and maybe, just maybe, peal the T87 PCB out of it's case and rehome it. Gotta sneak another small board into the mix, and why not just stack it all together in the same A50 footprint? Unless someone has a better spot to stick it ?
AI can't even spell Ya'll correctly.. So I sure the heck ain't letting it drive me around town yet. That would be to freaking weird... LOL But the name FUTCM, might actually fit if ya did..
HP does have DTCs mapped out on the T87 calibration that I have. I think the easiest method of mounting the TCM would be to use a mounting bracket from a 18-19 L5P truck. It has a nice flat bracket with two mounting points that could easily be attached to the fan shroud in the factory location. The TCM just snaps in place in the bracket. It's a nice, simple solution in my opinion. Here's the part number: 84402054
As for the spelling of the word "y'all/ya'll", I have to agree with AI on this one. No offense...
As for the spelling of the word "y'all/ya'll", I have to agree with AI on this one. No offense...
I Like it!!!What y'all think about this idea?
Feature
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Transmission
Control
Module
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How about this one...
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Cheap
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Thanks for the DTC update and part # Josh. Likely be easiest solution.HP does have DTCs mapped out on the T87 calibration that I have. I think the easiest method of mounting the TCM would be to use a mounting bracket from a 18-19 L5P truck. It has a nice flat bracket with two mounting points that could easily be attached to the fan shroud in the factory location. The TCM just snaps in place in the bracket. It's a nice, simple solution in my opinion. Here's the part number: 84402054
As for the spelling of the word "y'all/ya'll", I have to agree with AI on this one. No offense...
I couldn't find a picture of the bracket right off, so I ask Bing's AI for help. This is why I don't fear mid 90's IRC bots with the whole internet as a language library taking over the world anytime soon.. It's like asking a 6 year old to look it up on an Ipad 1 ...
None of those links actually have a picture you tool !!
In common search, side by side comparisons, generative AI still can't outperform Google's old AI scripts we've been surfing the web with for the past 30 years.. But it is a decent spell checker thesaurus, I must admit..
I'm not sure why there are no images on google if you search the part number, but I found these pics on a vendor website.
The two studs are there for a NOX sensor module to mount to, but they could easily be trimmed off if the are in the way of something.