The 2015 GMC Sierra 1500HD is part of the truck's fourth generation. It is a robust full-size pickup truck well-regarded for its performance and capability. It is offered in various trims including SLT, Denali, and Base. The base engine is a 6.0L V8 making 360 horsepower, and a more powerful 6.6L Duramax Turbo-Diesel V8 engine delivering 397 horsepower is also available. All are paired with a six-speed automatic transmission, and four-wheel drive is available. Standard features include a 4.2-inch color display, Bluetooth connectivity, and a four-speaker sound system. The Denali trim includes upscale features like an 8-inch touch screen, navigation, a Bose premium audio system, heated and ventilated front seats, and the Driver Alert package, which adds safety features such as a lane-departure warning and forward-collision alert.