Any reason a D1 brake would not function if it was in fact installed? Build sheet for this 80E says it has a D1 brake. Went to test it for the first time and nothing...truck rolls forward if I release the foot brake with the shifter in D1 and pressing the switch. Switch and wiring are good and if I drive in D2 and press the switch I can feel it shift to 3rd, so the switch is activating the 2-3 solenoid.

 

Is the line pressure maxed out in the tune?

 

No, it is proportional to torque and I did not get into the throttle when I tested it, so it was only at 100psi.

 

Something is wrong with it if it doesn't engage at 100 psi. I originated that design and unscrupulous builders have attempted to copy it with less than desirable results.

Maxxing out pressure will make it engage quicker but it will engage at 100 psi if properly done.