Designed for serious hauling, the Sierra is the workhorse pickup in the GMC lineup. The 1500 series model can be equipped with engines ranging from a 4.3L V-6 to a 6.0L V-8, all mated to a 4-speed automatic or 5-speed manual. Heavy-duty 2500 and 3500 series models offer 6.0L and 8.1L V-8 options, or a 6.6L Duramax® V-8 diesel. Transmission choices include a 4-speed and 6-speed automatics, or 5-speed and 6-speed manuals. A new Sierra 1500 hybrid model (with a 14 kW electric motor/generator) offers 10% increased fuel economy vs. the standard 1500 equipped with a 5.3L V-8. As an added benefit, the hybrid Sierra can be used as a portable electric power source to run 120V appliances or tools. Sierra trucks are available in 2WD or 4WD drivetrains. The luxurious Sierra Denali offers full-time AWD. As expected, these pickups can be equipped for serious towing capabilities, and have a rated GVWR of up to 12,000 lbs.