I remember one that claimed almost 500-ft-lbs/torque but forgot the name. I just quickly googled programmers for 2.8l Duramax and came up with this: Duramax Tuner Spade Tuner | Colorad and Canyon
Use Google and you'll find 'em
Of course when you write '2.8L' I'm thinking you mean 2.8L DURAMAX.
You wrote 'Vortec', and I'm not familiar with a Vortec 2.8L in this truck.
2016 Colorado 2.8L D-max, Crew Cab, Long Bed, Z71, 4WD.
ZONE 5.5" Suspension Lift
Moto Metal 970 17x8.5"
Nitto Terra G-G2s, 295/70/17