For much of GMC's history, the brand has shared engineering with the trucks of Chevrolet. GMC trucks stand out as a "Professional Grade" marque. The workhorse for the GMC brand has been the Sierra full-size pickup truck. In addition to the half-ton Sierra 1500, the 2500HD and 3500HD models provides serious hauling performance supported by upgraded powerplants as well as toughened transmissions. In recent years, luxury has become a focus for GMC trucks. First marked by the GMC Sierra C3 model, the expansion of the brand's Denali trim level was later introduced to the half-ton capacity truck as well as the HD models. The GMC brand has also been attached to smaller pickup trucks since the 1970s. After a brief hiatus, the GMC Canyon returned to the brand's line-up in 2015.