The 2009 GMC Sierra 1500 half-ton, full-size pick-up was redesigned in 2007. It is based on the basic design platform of the Chevrolet Silverado 1500, and is available in Regular Cab, Extended Cab, and Crew Cab versions. For 2009, the GMC Sierra 1500 includes a gas/electric hybrid model; a new 6-speed automatic transmission; and the Sierra All-Terrain off-road package, which includes a leather interior; exclusive exterior trimmings; brushed aluminum highlights on the dash; Rancho monotube shock absorbers; skid plates; and 18-inch chrome wheels. Three bed lengths available are: the 5-foot 8-inch short bed; the 6-foot 6-inch standard bed; and the 8-foot long bed. All configurations are available in two or four-wheel drive. The Sierra 1500 comes in four trim levels: Work Truck, SL (Crew Cab only), SLE, and SLT.

The Sierra Extended Cabs have rear-hinged back doors for better access; Regular Cabs offer seating for up to three passengers, while Extended and Crew Cabs can seat up to six. The Sierra 1500 is redesigned with a stronger and stiffer fully boxed frame, improved exterior fascia, and a more spacious cabin. The truck is marked by a unique hood; steeply raked windshield grille; front fenders; headlights; taillights; and reduced body gaps. The 2009 GMC Sierra offers two styles in interior accommodations called "pure pickup" and "luxury inspired". The XFE version has special wheels and tires, as well as mechanical and aerodynamic components. Standard equipment on the Work Truck include air conditioning (Extended Cab, Crew Cab); OnStar system; AM/FM/CD/MP3 player; satellite radio; tilt steering wheel; vinyl upholstery; front split bench seat; folding rear seat (Extended Cab); split folding rear seat (Crew Cab); rear-hinged rear doors (Extended Cab); front-hinged rear doors (Crew Cab); power door locks (Crew Cab); remote keyless entry (Crew Cab); tachometer; intermittent wipers; cargo-box light; automatic headlights; and vinyl floor covering. Higher trim levels add more upscale features.

The Sierra 1500 has eight engines and five suspension choices in its line-up. Depending on the cab-bed configuration, the available engines include a 195-hp 4.3-liter V6; a 295-hp 4.8-liter V8; a 315-hp 5.3-liter V8; a 367-hp 6.0-liter V8; and a 403-hp 6.2-liter V8. The 5.3 liter and 6.0 liter V8 engines get GM's Active Fuel Management cylinder deactivation. The V6, 4.8-liter V8, and the 5.3-liter V8 engines are teamed to a 4-speed automatic transmission; the 5.3-liter V8 Crew Cab and the 6.0-liter V8 receive an optional 6-speed automatic. Some of the 5.3-liter V8 and all the 6.2L V8 engines can run on E85 ethanol-blended fuel. Rear-drive Sierra models with the 5.3-liter V8 and the 6-speed automatic can be configured as an XFE model, which stands for Xtra Fuel Economy. According to GM, XFE versions get an increase in fuel economy of up to 7 percent over non-XFE versions. Also part of the Sierra line-up is the Denali Crew Cab with the 6.2-liter V8 and exclusive interior and exterior highlights. The Sierra 1500 has a maximum towing capacity of 10,700 lb.

Standard safety equipment includes dual front airbags; seat belt pre-tensioners; anti-lock brakes; LATCH child-seat anchors; anti-skid system with rollover sensors (on Extended Cab 8.1-ft bed and Crew Cab); a tire-pressure monitor; and daytime running lights. The Sierra 1500 earned a five-star frontal crash-test rating. GMC new-truck buyers get a one-year subscription to the OnStar Safe and Sound Plan; OnStar can report crash data to emergency services. The Sierra offers roof-mounted side curtain airbags as on option on the SLE and SLT. Electronic stability control is standard on V8 models. Ultrasonic rear parking assist is optional on all models.