GMC updated its complete line of full-size Sierra pickup trucks for the 2003 model year and incorporated a new electrical architecture. While this General Motors division positions its trucks as “professional grade,” the similar Chevrolet Silverado ranks as the high-volume member of the duo.
Sierras are available in half-ton 1500, three-quarter-ton 2500HD and one-ton 3500 forms. No regular 2500 series exists, but a 1500HD is offered. Whereas the higher-rated models provide an increased level of hauling and towing capabilities, the 1500 series offers editions that aren’t available in the others, like the Sierra Denali luxury pickup.
For 2006, GMC’s Sierra Hybrid expands to nationwide availability; it previously was offered only in select markets. Though its electrical motor does not actually propel the vehicle, GMC still classifies it as a hybrid
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