Pickups were always the workhorses of the road, hauling gear and other materials through some of the toughest terrains. They were built large and were made to last. The GMC Sierra 2500HD is a testament to the robustness of these vehicles. The 2500HD is the heavy-duty variant of the Sierra 2500 light truck.
1999: Prior incarnation as the Sierra 2500
Before the Sierra 2500DH, there was only the Sierra 2500, a light-duty pickup truck meant for regular hauling jobs and for driving through flat city streets. In 1999 and 2000, a heavy-duty version of the 2500 was introduced. The light duty was soon discontinued while the heavy-duty version would be offered alone as the new 2500HD.
2001: The first release of the Sierra 2500HD
The first 2500HD came equipped with a 6.0 liter V8 engine capable of producing 300 horsepower. It also came with either a standard five-speed manual transmission or an optional four-speed automatic transmission. Two other optional engines were offered as well: the 8.1 liter V8 gasoline engine capable of producing 340 horsepower and a 6.6 liter turbodiesel engine capable of producing 300 horsepower.
The powerful engines that came with the 2500HD are what made the pickup give such an impressive performance. The towing capability of the truck was phenomenal while the acceleration was much better than other trucks of the same category and weight class. There was a lot to be desired with the truck's interior design but since it was designed mostly as a workhorse, there was little room left for aesthetic improvements.
2007: The Second generation
The Sierra 2500HD came in three body types: regular, extended and crew cab. The extended body type featured additional space behind the front seat for three more passengers. The rears doors were smaller than those in the front and the interior space in the back was mostly cramped. The crew cab type had an enlarged interior in the back providing a generous amount of space for passengers and four full sized doors for the truck. All 2500HD's were powered by a 6.0 liter V8 engine that could produce 360 horsepower. A 6.6 liter Duramax turbodiesel V8 that could crank out 397 horsepower was offered as an optional engine. All trucks were fitted with a six-speed automatic transmission. The regular body type was available in two basic trims: the work truck and the SLE. The extended and crew cab body types had the two basic trims with the addition of the SLT and the Denali.