I bought my truck about a year ago and it came with the mini maxx and deletes already done. Since owning it the manual shift +/- button has only worked for downshifting and not the upshift. I first assumed it had something to do with the mini maxx withought the overdrive program loaded. I bought the overdrive unlock code and loaded it (so far pleased with it) however the problem is still there, i cannot upshift. Has anyone else dealt with this or know of how to fix this?

 

Sounds like it is correct to me....You can force a downshift by toggling minus....and when you toggle up it just sets a new high limit...and like any automatic it will upshift when it senses conditions are correct.

 

does the gear selection indicator change when you push the up button? if so then it is working as it should, you cant force it to upshift with the button, only down