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Thread: Medium duty trucks 8.1l with allison

  1. #1
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    Default Medium duty trucks 8.1l with allison

    Hey Guy's,
    First all thanks for all the wonderful knowledge that a lot of you know, I have been lurking on the site for years, and silently with your help I have fixed and programmed a lot of things that I wanted to change, However I am running into a problem.
    I own my own business with several GM c4500, c5500, c6500 medium duty trucks, They all have the 8.1l engine and Allison trans , some 5 speed some 6 speed, I have been told that if you turn off the torque management system the truck has a lot more power. And while these trucks are pretty good, and I personally like the 8.1 I need some info on where and what all parameters do I change to turn TM off, My trucks are not hot rods' just could use a little more ump ! I know I was told that TM robs the power it all ready has, and I can see that because of wanting to protect the ALLY. but these trucks have the LRW option, which is 325hp . Any info and direction would be helpful, thanks again.

  2. #2
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    Post your ECM and TCM tunes up, or at least 1 set from a truck. Im not sure I'd recommend removing all the TM from this combo initially, but you could probably work into it as the Allison behind an 8.1 shouldnt have any problems handling all the power.
    ~Erik~
    2013 Sonic RS Manual - 1.4L I4T E78, tuned, turbo mods, etc.
    2008 TrailBlazer SS 3SS AWD Summit White - LS2 E67/T42, bolt ons, suspension, etc.
    2002 Chevy TrailBlazer LT 4X4 Summit White - 4.2L I6 P10, lifted, wheels, etc.

  3. #3
    Joe (Moderator) joecar's Avatar
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    TM usually enables in abuse mode, i.e. when you power-brake or shift into gear with throttle planted (i.e. engine RPM climbs out of proportion to VSS while in gear).

    TR enables during shifts, it momentarily tapers the torque output to protect the clutches (I don't know if Allison has this).

    It would be best if you can make them work for you.

  4. #4
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    thanks

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