Chevrolet's 2009 2500HD and 3500HD are heavy-duty versions of the Silverado pickup, all of which were completely redesigned back in 2007. The HDs are available in three cab styles (Regular, Extended, and Crew Cab) and two box configurations (standard and long). Extended Cab models come with smaller rear access doors that open 170 degrees and have fully opening windows. Crew Cab models come with four full-size doors. 3500HD models come in two additional variants, identified by SRW (single rear wheels) or DRW (dual rear wheels). The DRW models offer enhanced stability for those who routinely tow trailers near the upper end of capacity. Two suspensions are now offered on the HD trucks. The Z85 suspension is standard, and the optional Z71 suspension is oriented toward off-road duty and includes skid plates, along with other additional equipment. Compared with the light-duty Silverado, the HD has a larger, bolder appearance, especially in front, with a wider grille, domed hood and broader fenders. The HD trucks boast a ladder frame, a hydroformed front section, a structure designed for better crash protection, recirculating-ball steering gear aimed at improving steering feel, and a strong 4-wheel anti-lock disc brake system. The brakes also include an integrated trailer brake controller. Like the light-duty Silverado, the HD versions of the Silverado get two completely different interiors, depending on the intended use. The WT (Work Truck) and LT models, intended more for fleet work, come with a simplified instrument panel with large, functional controls, under-seat storage, and a cavernous double glove box. Amenities such as Bluetooth hands-free connectivity are now available. XM satellite radio comes standard. The luxurious LTZ, intended for those who might interested in towing in style, comes with an interior that rivals that of luxury SUVs, with a larger center console, heated leather bucket seats and chrome trim. A 6.0L gasoline V8 engine with variable valve timing, making 353 horsepower and 373 ft-lb of torque, is standard on both models, and a 6.6L Duramax diesel, making 365 hp and 660 ft-lb, is optional. Both engines are mated to 6-speed automatic transmissions, and the Duramax is designed to be able to run on biodiesel fuels. Standout optional features on the LTZ include heated windshield washers, power-adjustable pedals, Ultrasonic Rear Parking Assist, a rear-seat DVD entertainment system on crew cabs, an EZ Lift tailgate, a Universal Home Remote and a power-sliding rear window on Extended and Crew Cabs. A variety of audio systems includes MP3- and DVD-compatible players. Driver and passenger front airbags are standard across the range, as is a tire pressure monitor and GM's OnStar system, while StabiliTrak stability control with Proactive Roll Avoidance is standard on Extended and Crew Cabs.
