Key in "run" position truck not running .....
Emergency brake set ....
Select level via shift indicator position "1" being level 1 Juice ....
Ditto for Tow Haul ....
Once level selected push GO peddle to floor two consecutive times .... Take your time insure your getting full throttle movement ....
Repeat in T/H ....
"R" is for zero ....
Place in park ...
Cycle Tow Haul button on and off prior to restart ....
Restart truck, check confirmation,reg and T/H ... Number of short engine burst represents level of performance tune ....
I think that's about it, I haven't changed mine in months ...
Mac