Results 1 to 3 of 3

Thread: Tow Haul...Zero Throttle...Downshifts

  1. #1
    Lifetime Member killerbee's Avatar
    Join Date
    Jan 2006
    Posts
    1,059

    Default Tow Haul...Zero Throttle...Downshifts

    OK, been wanting to post this for awhile now. There is something else we need access to. Just can't put my finger on it.

    When off the pedal, the zero throttle setting does nothing. If I give it just a smidge of throttle, the downshift table kicks in. This is especially obvious with the 5-4 shift. I suspect it has to do with the grade braking downshift algorithm. IOW, it seems that the downshift schedule is governed by other tables we don't have (yet )

    Ross, can you help?
    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"

  2. #2
    Lifetime Member THEFERMANATOR's Avatar
    Join Date
    Mar 2009
    Posts
    794

    Default

    I believe all of the zero throttle downshifts are contained in other tables as I know teh lock-up zero throttle table doesn't respond properly in regular mode.
    1995 GMC 2500 SUBURBAN powered by 01 DURAMAX/ALLISON, little of this, a little of that,
    DIAMONDEYE 4" exhaust, CORSA muffler, AFE stage 1 dry filter, custom tuning by me, KENNEDY single pump and pump rub kit.

  3. #3
    Lifetime Member killerbee's Avatar
    Join Date
    Jan 2006
    Posts
    1,059

    Default

    The zero throttle downshift works (clarification). But only if the speed is below the zero throttle entry when you take your foot off the pedal.

    I will post an example in my next post, in hopes that we can finally get to work on this. It has been an "accepted" limitation for a long time, and I want to generate some interest/motivation to resolve it. I have done a lot of testing thus far. I am buying a couple of TCM streams on faith.
    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"

Similar Threads

  1. tow/haul mode?
    By THEFERMANATOR in forum Conversions / Aftermarket Parts
    Replies: 7
    Last Post: February 3rd, 2010, 06:43 PM
  2. Tow/haul mode
    By rennoc442 in forum 4speed RWD/FWD Transmission Tuning (incl T42)
    Replies: 0
    Last Post: July 21st, 2009, 07:31 AM
  3. tow/haul transition
    By Ritch in forum 4speed RWD/FWD Transmission Tuning (incl T42)
    Replies: 0
    Last Post: June 4th, 2008, 03:01 PM
  4. Tow/Haul mode?
    By N0DIH in forum Vortec V6/V8 Specific
    Replies: 5
    Last Post: March 27th, 2007, 06:23 AM
  5. Tow / Haul
    By mcwarren in forum Custom Operating Systems
    Replies: 1
    Last Post: February 28th, 2006, 05:39 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •