4l80e false shifting help
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Joined: Jul 2010
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From: VA
4l80e false shifting help i swapped a 6.0L and 4l80e into an 87 k5 blazer, once i got a correct 4l80e ECU i thought i had everything good, i changed some shift points and gave it a drive around, it instantly kept popping code (ether 0758 or 0748) cant remember and i turned it on and to no error dected, took it out on a drive and drove great, shifted normal, down shifted as should etc, ended up popping code 0758 or 0748 after about 2 miles ish, i took note of the code and turned truck off, cleared DTCs and restarted it and drove it home no issues, gunned it made it down shift etc, got home and tryed turning that code to no error detected and it would be stuck in 2nd gear but in hptuners would show it shifting into 1st 2nd 3rd like it was shifting normal but the truck actually wasnt shifting, not liking this at all i went back to the previous tune and did the same thing, i loaded in the factory 2500HD tune and same thing, i cant get it out of 2nd no matter what, and it says it shifts 1st to 2nd and its really just taking off in 2nd and stayin in 2nd.
did i screw something up bad by turning off that 2nd code?
any insight or anything is much appreciated
thanks!
heres a link to a thread i already made in HPtuners
http://www.hptuners.com/forum/showth...ne-now-nothing
did i screw something up bad by turning off that 2nd code?
any insight or anything is much appreciated
thanks!
heres a link to a thread i already made in HPtuners
http://www.hptuners.com/forum/showth...ne-now-nothing
