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Thread: flashing 6spd allison os into 5spd allison tcm

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    Default flashing 6spd allison os into 5spd allison tcm

    has any one done this conversion on a 5 spd Allison taking the 5 spd tcm and flashing a 6spd os into the tcm and making it work

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    Lifetime Member Cougar281's Avatar
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    Nope. Can't be done. The 5-speed and 6-speed TCMs are totally different. Only way to do it without suncoasts hacked TCM is to convert from lb7/lly to all LBZ electronics, top end and trans.

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    guess time for me to sit done and figure it all out. cause how suncoast and two other companies sell it all day long and ask for a 5 spd tcm as a core in return. time to sit down and figure it all out. just saying.

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    Yep, electronics communicate differently


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    Lifetime Member Cougar281's Avatar
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    Quote Originally Posted by Scarface View Post
    guess time for me to sit done and figure it all out. cause how suncoast and two other companies sell it all day long and ask for a 5 spd tcm as a core in return. time to sit down and figure it all out. just saying.
    Those are some kind of 'hacked' calibration and a custom VB. You cant just run a 2006+ 6-speed VB with a 3rd gen TCM. It'll never be right. I tried it.

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    Lifetime Member Chavez91's Avatar
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    Its not to hard to get it going. The part that is going to kill you is getting it calibrated. Shift quality calibrations are what will make or break your 6 speed conversion. Fleece and Socals calibrations SUCK IMO as im sure they had no idea what tables are actually involved and what they actually adjust. The 5 speeds have provisions for 6th gear. But most 6 speed stuff is either blank or disabled.
    Josh

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    Lifetime Member THEFERMANATOR's Avatar
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    Quote Originally Posted by Scarface View Post
    guess time for me to sit done and figure it all out. cause how suncoast and two other companies sell it all day long and ask for a 5 spd tcm as a core in return. time to sit down and figure it all out. just saying.
    They use a 5 speed TCM, but it is NOT a factory 6 speed TCM tune. The 6 speed TCM is a GEN IV a40 or newer style TCM. The 5 to 6 speed conversion kits use a 5 speed TCM tune that has been hacked to add in 6th gear. It has NOTHING in common with a factory 6 speed tune or TCM other than it has 6 gears. There is another tuner out there who used to sell the 6 speed tune, and you could use a 6 speed valve body and modify the tune file to operate the newer lockup solenoid(drop max duty cycle back from 99% or whatever it is back to 67% which is max for the stock 6 speed solenoid) and make it work as quite a few people did it. It was a hacked copy of the 04.5-05 conversion kit, so you had to do something about the missing G solenoid if you used it in a LB7, and there was no way to lockout 5th if you put it in an 01-02.
    1995 GMC 2500 SUBURBAN powered by 01 DURAMAX/ALLISON, little of this, a little of that,
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    Lifetime Member killerbee's Avatar
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    Quote Originally Posted by Scarface View Post
    guess time for me to sit done and figure it all out. cause how suncoast and two other companies sell it all day long and ask for a 5 spd tcm as a core in return. time to sit down and figure it all out. just saying.
    I can provide a 6-speed AL5 (01-05) TCM, with or without a core. PM me if that is the direction you want to go.
    Michael, Systems Engineer 04.5 D-max LLY, Phoenix, Arizona Email
    Custom Tuning Services
    DURAMAX/CUMMINS ECM's TCM's for sale, all years, 20% wholesale discount available
    EFILive's first VGT "Software Wastegate Tune"

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    it is on a 05 lly truc. pm u killer bee

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