Need a little insight on tuning for jakes transbrake on a 4l80e with hp tuners....I was told the computer should not command the 1-2 shift, that you had to manually shift it from first to second...Well i have an automatic valve body anyone know how i should tune for this? Thanks for any help in advance

 

You don't want to allow the PCM to command an upshift when in manual low.

Some PCM's and tuning programs allow you to tune this, some don't.

You must be in manual low to operate the transbrake. It keeps it safer so it cannot be accidentally engaged at highway speeds and also allows it to engage quicker.

So you launch in manual low, release the transbrake and immediately upshift to 3rd gear and let the PCM shift the trans, or just manually upshift through the gears.

 

Jakes with trans brake! WWOOHHOOO thats all... cannot wait!