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Thread: T42 4L60E 3-4 UpShift issue

  1. #1
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    Default T42 4L60E 3-4 UpShift issue

    So been trying to help a buddy out with his truck.
    08 E38/T42
    Heads/cam 6.0
    Rpm level 6 4L60E
    4.10 gears

    It is shifting 3-4 at WOT.
    No matter what MPH/RPM I put in the tune, it shifts at the same mph (about 100mph) every time.
    Even in manual 3rd, set tow/haul to max rpm/mph and even tried Bi-Di control to hold 3rd gear and it still shifts into 4th.

    I'll try and post log/tune in a little while.

    I'm not too familiar with T42 tuning as much as I am with LS1B tuning so I may be missing something?


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  2. #2
    Joe (Moderator) joecar's Avatar
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    Check that the Throttle Kickdown tables are all set to 100% all across.

  3. #3
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    I completely forgot to post the tunes.... I'll try and do that tomorrow at lunch.
    The flexplate broke so truck is down getting transmission freshened up and new Torque converter. So maybe in the next couple weeks I can get more time to tinker with it.

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  4. #4
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    Here is the original tunes that were on the truck.
    Startup was crazy with all the air they had in the tune. It would rev to 4000rpms.
    Attached Files Attached Files

  5. #5
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    Quote Originally Posted by joecar View Post
    Check that the Throttle Kickdown tables are all set to 100% all across.

    Im not seeing any of the throttle kickdown tables in this T42.

  6. #6
    Joe (Moderator) joecar's Avatar
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    I'm looking thru your T42 file...

    I'm checking that none of the shift curves cross anywhere.

  7. #7
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    Should be able to get back to the truck this weekend to try out a stock tune with slight adjustments to see what happens.

  8. #8
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    The transmission builder is tryin to sort it out with HP tuners and not having any luck.
    I think it would be best to just start over with a stock tune and flash it in.

    Can I do a full flash of the same OS with a T42?

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