2002 GMC Sierra 2500HD Reviews"Sierra HD similar to Chevrolet Silverado HD; both are redesigned for 2001 along the lines of lighter-duty 1500/2500 models. This report covers mainstay 3/4-ton 2500HD and 1-ton 3500 pickups, though chassis-cab and chassis cutaway models are also offered.
Both HD Sierra models are available with rear-wheel drive or 4WD that must be disengaged on dry pavement but includes low-range gearing. Optional on 2500 is General Motors' Autotrac 4WD that can be left engaged on dry pavement; 3500 offers optional electric-shift transfer case. HD series comes in choice of regular cab, extended cab with rear-hinged back half-doors, and Crew Cab with four full-size front-hinged doors. All can be ordered with front bucket seats or a 40/20/40 split bench. The extended and Crew Cab include a three-person rear bench. Sierra 3500s come only with an eight-foot cargo box ; 2500s offer a 6.5-foot box as well. All 3500s are ""duelies,"" with dual rear wheels on each side.
All models have standard dual dashboard airbags, ABS, 4-wheel disc brakes; some offer GM's OnStar assistance system. Base engine is a 6.0-liter V8. Optional are a new 8.1-liter V8 and new 6.6-liter Duramax turbodiesel V8. Base engine teams with 5-speed manual transmission or optional 4-speed automatic with Tow/Haul mode. The two larger engines have a new 6-speed manual or newly optional 5-speed Allison automatic with Engine Grade Braking, an electronic feature that makes an automatic downshift when descending steep slopes. Payload and tow ratings are claimed to be best in class. Sierra HD performace and accommodations mirrors those of Chevrolet Silverado HD."