The 2006 GMC Envoy Denali 4dr SUV 4WD has a 5.3 L, 300 hp V8 engine with 4 speed automatic transmission.  Gas mileage comes out to 15 mpg in the city and 21 on the highway.  This trim has 4 doors, seats 5, and offers standard air conditioning, power windows, power door locks, power/leather seats, cd player, ABS brakes, traction control, and stability control.  Options include navigation system and sunroof.  Towing capacity goes up to 6500 lbs.