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Thread: TCC release help?

  1. #1
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    Default TCC release help?

    Going through the Appalachian mountains has my 5.3 Envoy downshifting quite often, I'd like to restrict the downshift to a TCC release only if possible. Anyone out there know how to keep this transmission in fourth and unlock the torque converter so it will help save mileage. I know GMs used to do this years ago and it seems they took the easy way out and left that tuning out.
    Mine2001 GMC 2500HD EC/LB, D/A. 4in MBRP exhaust, AFE Stage II w/Amsoil Ea air filter, ISSPRO boost/Pyro guages, PPE Boost Valve, EFI Live V2, Maximum OD Stage 2 Trans, Amsoil throughout, AirDog150, modded intake horn.

    540HP/1056TQ
    Dyno'd Danville Performance
    April 5th 2011

    Hers: 2006 GMC Envoy XL Denali, Flowmaster 40 with a bullet style resonator in the back, EFI Live with the help of JoeCar and other great members here.

  2. #2
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    Mine2001 GMC 2500HD EC/LB, D/A. 4in MBRP exhaust, AFE Stage II w/Amsoil Ea air filter, ISSPRO boost/Pyro guages, PPE Boost Valve, EFI Live V2, Maximum OD Stage 2 Trans, Amsoil throughout, AirDog150, modded intake horn.

    540HP/1056TQ
    Dyno'd Danville Performance
    April 5th 2011

    Hers: 2006 GMC Envoy XL Denali, Flowmaster 40 with a bullet style resonator in the back, EFI Live with the help of JoeCar and other great members here.

  3. #3
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    Default

    First thing to do without even looking at the tune is to use SSpddemon's A4 Trans worksheet (it's stickied) and make sure all the up/downshifts are configured per his logic. It makes the transmission not "think" or wait between TCC unlocks or downshifts, just operates smoother IMO. Then you can use it to overlay the 4th TCC lockup curve with the 4->3 downshift and configure to your liking.
    ~Erik~
    2013 Sonic RS Manual - 1.4L I4T E78, starting the mods
    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.

  4. #4
    Joe (Moderator) joecar's Avatar
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    Lower (and shift right) the 4->3 shift curve to hold off the downshift.

    ~ posted by phone ~

  5. #5
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    Default

    I'm not particularly looking to hold off the shift as much as I'm looking for the Torque Converter to release rather than a full gear kick down. Does that make sense and would it save fuel in the long run or will I just end up chasing my tail?
    Mine2001 GMC 2500HD EC/LB, D/A. 4in MBRP exhaust, AFE Stage II w/Amsoil Ea air filter, ISSPRO boost/Pyro guages, PPE Boost Valve, EFI Live V2, Maximum OD Stage 2 Trans, Amsoil throughout, AirDog150, modded intake horn.

    540HP/1056TQ
    Dyno'd Danville Performance
    April 5th 2011

    Hers: 2006 GMC Envoy XL Denali, Flowmaster 40 with a bullet style resonator in the back, EFI Live with the help of JoeCar and other great members here.

  6. #6
    Joe (Moderator) joecar's Avatar
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    You want the 4th gear TCC release to occur before the 4->3 downshift...

    so you have to position the 4th gear TCC release curve above the 4->3 downshift curve (and make sure they do not cross)...

    then you fine tune by doing this:
    - move the 4th gear TCC release curve up/left (to make this event happen sooner)
    - move the 4->3 downshift curve down/right (to make this event happen later)

    ( while doing this you must make sure that the 4th gear TCC release curve does not go above the 4th gear TCC apply curve... be careful, yours are very close to each other )


    As Erik said, use the spreadsheet to space out the curves and make sure that none of them cross any others.

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