Hi Guys, Diablo emailed me this morning to announce that they've got their tuner units ready for the 2014's, here are some of the options it does, I've had a Diablo for my 2010 Denali since I purchased it, but back then there were a lot fewer things supported than they appear to be doing now (primarily purchased it to change the tire sizes and disable the limiter)
inTune really improves the 2014 GM Truck; tunes included are 87 octane tune, MPG Booster Tune, and the Diablo tune, which should be used with octane higher than 91. Increases of up to 15 hp and 20 ft lbs of torque can be seen across the entire RPM range with the Diablo Tune.
Our tunes are calibrated specifically to improve performance, drivability, and economy and reduce the factory's power-robbing "torque management" to put more power to the ground when you need it. Other options include TCM (Transmission Control Module) control to adjust automatic shift characteristics, DOD (Active Fuel Management) disable, speedometer adjustment for gear and tire changes, and raising speed and rev limiters.