Adding part-time four-wheel drive to the 2006 GMC Sierra 1500HD SLE1 4WD offers more stability in tough road situations, but shaves a few pounds off towing capacity -- down to 9900 pounds from 10,300. The 4WD comes with automatic locking hubs and joins the front stabilizer bar, front independent and rear live axle suspension, and 16-inch wheels with all-season tires for truck-like handling and ride. 4-wheel disc and ABS brakes, automatic headlights, foglights, and dual front airbags earn three and four-star frontal impact ratings and four-star side impact ratings in crash tests. An auto-dimming rearview mirror, folding mirror extensions, turn signals in mirrors, and a locking rear differential are available as options.
Six people fit in two rows of seats in the 2006 Sierra 1500HD SLE1, a half-ton pickup with a 6.5-foot bed. Rear seats split-fold, and the bed can be outfitted with tie-downs, a net, a bed extender, and a cover. A sliding rear window can replace the fixed one. Standard interior features include a full power setup, keyless entry, cruise control, a CD player, intermittent wipers, heated mirrors, privacy glass, temperature display, and a security system You can add OnStar, a power driver's seat, automatic climate control, wheel-mounted audio controls, satellite radio, a trip computer, and leather seats.