The standard features of the GMC Sierra 3500HD Pro include 6.6L V-8 401hp engine, 10-speed automatic transmission with overdrive, 4-wheel anti-lock brakes (ABS), Side seat mounted airbags, Curtain 1st row overhead airbag, Airbag occupancy sensor, Air conditioning, 18" steel wheels, ABS and driveline traction control, StabiliTrak w/Proactive Roll Avoidance electronic stability, Power windows