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schroedj
May 1st, 2018, 09:29 AM
I have searched this forum for any sign of support for an A42 TCM without success
Would I be able to tune my A42 TCM with EFI Live?
Attached is the CIN info
Thanks in advance, Jerry

GMPX
May 1st, 2018, 09:56 AM
Probably no, not even sure what the A42 is in the range of Allison TCM's. Is that on Silverado's or non GM vehicles?

schroedj
May 1st, 2018, 11:05 AM
Thanks for the reply
The A42 would be non GM. It is an Allison TCM for a stand alone 1000 in an industrial application.
Will try to connect but looking at the CIN details I will probably not waste too much time playing around with it...

GMPX
May 1st, 2018, 11:51 AM
I'm guessing given the application the A42 is probably J1939 only, the Allison tuning and communications in EFILive is for GM vehicles only.

schroedj
May 1st, 2018, 11:54 AM
It is J1939 for sure so I will not waste any time in that case.
Thanks again,
Jerry

TwistedDiesel
March 3rd, 2020, 10:42 AM
All 4th gen TCMs have CAN1 J1939 and CAN2 GMLAN connections. I have a couple T42s I have wished were supported, they detect and read with EFI live just fine but of course the OS is unsupported. I hoped and assume that the mapping is identical to the A40 and that it would just be a OS number being added to a definition list, I dunno :nixweiss:

I can get a read and post it here if its worth you guys time to see if it's that easy.

Medium duty Allison tuning is becoming important with the HD Cummins tuning being available now.

GMPX
March 3rd, 2020, 11:13 AM
We did get a few Allison TCM's last year to look over (A41, A43, A51, A53), one of them had Allison software in it but no identifier of what OS or Cal was in it, there was nothing.

I am sure the mapping or at least the control concepts would be similar to the GM versions but that doesn't mean it would be simple task by any means.

cadillackid
March 4th, 2020, 01:14 AM
+1 for interest in A51.

I have an A41 that I tune with EFI all the time and it seems pretty accurate.. im not sure in my application where the Pattern A,B,C,D apply however im able to edit the shift points and TCC parameters without issue.. it as mentioned before.. CAN1 is J1939 and talks to my Navistar T444E ECM for throttle and engine load info.. CAN2 is GMLAN and where I talk to EFI from.

I did a read / flash with Allison PCCS to copy and write my calibration to another A41 TCM which tyhen became tuneable with EFI after I reflashed it.. so it seems A41 works whether officially suppoorted or not..

I have an A51 whuich EFIlive can read the "dashboard" however I have no ability to read / write the Cal on it.. Id rather be running my A51 as it supports J1939 TAP shifting. whereas my A41 does not.. my A41 is aware the J1939 is being sent, however the allison Datapoint "wire" isnt mapped to a function in that TCM where it is in the A51..

my allison DOC premium and PCCS dont allow me to add / delete wires / datapoints or edit the calibrations..

-Christopher