The GMC Sierra pick-up trade has long been popular among landscape and irrigation contractors. The reasons? As GMC points not at home Sierras are not solitary strong and durable, but they give you a wide range of choices: the 1500 2500 HD (heavy duty) and 3500 This year, the 1500HD type returns, along with the Hybrid (10% more firing economy, available only in near Western states) and the band Cab Denali. just discovered for 2005: * 17-inch wheels and tires onward most 1500 models; * power increase for Duramax 6600 66L turbo-diesel co 310 hp and 605 lb-ft of torque (automatic transmission