Trans slip

[crazyatvdude09]

i bought my truck and a month later the trans starts slipping between 1-2. after a while its completly gone and wont shift i take to my local for house and we put a reman trans in (partly because i didnt want them to re-build it) after the new trans was put in i ran it stock for a month or two. then got NEW custom tunes 3-4 months later the same slip from 1-2. right now its only under WOT when it tries to shift from 1-2 it goes into "neutral" until i let off the throttle then shifts then i get the same thing between 3-4.
so at this point iv put a new trans, new tunes and im still comeing up with the same issues. i dont run the truck hard just normal daily driving..? what gives could it possibly be the trans computer?
the re-man trans has a warrenty but i know they will void it if i tell them im running a tuner

[crazyatvdude09]

also the truck has always gotten crappy mpg's 10-13 with or without tunes and also loaded or un-loaded no matter the conditions it stays the same, shi**y

[paradiserfd815]

I have the same issue with a stock trans. It seems to shift into neutral at wot only with my xstreet or xrace tunes. Any other amount of throttle the trans shifts fine. Towing and basically any other throttle position is very solid shifting with no flare at all. I have my shift pressures up'd 15% and the only time it happens is when the pedal is as far as she'll go. Also if I work up to a wot throttle run, first half throttle run, then 3/4 and then wot it seems to shift fine. I've had people tell me it's a learning curve, it's a torq converter or it's a solenoid. I'm going with the learning curve bit because I am able to fix the problem with the right workup strategy. I believe a converter or solenoid would make the issue happen every time. Mine will do it when I put a fresh tune in and don't let it adapt, if I drive easy for awhile and then wot, or if I get to much wheel spin at launch.

[russf]

Usually when you install a tuner there is a tranmission relearn needed, don't know if you guys knew that.. Doesn't mean that this is your problem either tho

[paradiserfd815]

I think mine is a learn issue but why does it do it after a tune has been installed for awhile. Does your does the truck get used to your granny driving and then forget how to shift when you wot it? I'm in the 450-500hp range if that matters.