The 2019 GMC Sierra 1500HD, belonging to the third generation of Sierra trucks, is a full-sized pickup geometrically designed to showcase muscular and rugged charm. It offers two engine options - a 5.3L EcoTec3 V8 that generates 355 horsepower, and a 6.2L EcoTec3 V8 that puts out an impressive 420 horsepower. Both engines come mated to a 6-speed - or optional 8-speed - automatic transmission, with rear-wheel standard and four-wheel drivetrains available. Offered in five primary trims: Base, SLE, SLT, AT4, and the luxurious Denali, the Sierra 1500HD provides a variety of options for customization. The truck features the GMC Infotainment System with modern amenities including a 7- or 8-inch touchscreen, Apple CarPlay, Android Auto, and a 4G LTE Wi-Fi hotspot. Safety highlights include StabiliTrak stability control system, ProGrade Trailering System, and available driver assist technologies such as frontal collision warning and lane keep assist. Outside notable improvements in 2019 include the MultiPro tailgate that offers six unique functions and positions for enhanced flexibility.