2018 F150 won't command a 1-2 shift using a transbrake (transbrake is using an outside box, not the tune). I've lowered all the output shaft speeds and well and wot rpm to a very low value and still nothing. I can foot brake the truck and it will short shift, so I know it can do it. The truck makes 700 on the blower and this is all leaving in 4wd, so no tire spinning issues. Anybody have any ideas before I set it up to leave in second?