The 2006 Chevrolet Silverado 2500HD LT2 4dr Extended Cab SB 4WD has a 6.0 L, 300 hp V8 powertrain with standard 4 speed automatic transmission.  This trim has 4 doors, seats 5, and offers standard air conditioning, power windows, power door locks, power seats, cd player, and ABS brakes.  Options include leather seats and sunroof.  Finally, max towing capacity comes out to 15600 lbs.