LIVE: 2020 GMC Sierra HD

The HD can tow "well in excess" of 30,000 pounds.

GMC waited until the week after the 2019 Detroit auto show to unveil the 2020 Sierra Heavy Duty online.

As always, the Sierra 2500 Heavy Duty and the Sierra 3500 Heavy Duty are closely related to the Silverado Heavy Duty under the sheet metal. The two trucks look more different than ever before, though. Bigger than its predecessor, the Sierra Heavy Duty wears a tall, upright grille that stretches into headlights with C-shaped LED inserts. Designers chiseled a functional scoop into the hood to direct cooling air to the turbodiesel engine.

Out back, the bed sits an inch lower than in the outgoing Sierra to facilitate the task of loading and unloading bulky items. GMC's six-way MultiPro tailgate is either standard or optional depending on the trim level selected. Buyers seeking convenience can also order steps in front of the rear wheel wells.

The Sierra illustrates the pickup segment's shift towards more high-tech interiors. It notably offers a 15-inch head-up display that places key information including the vehicle's speed, navigation directions, and an inclinometer right in the driver's line of sight. The infotainment system is compatible with Android Auto and Apple CarPlay.

Though full technical specifications haven't been released yet, we know GMC will offer the Sierra HD with a 6.6-liter turbodiesel engine rated at 445 horsepower and 910 pound-feet of torque. Bolted to a 10-speed automatic transmission, the turbodiesel lets the Sierra HD tow "well in excess" of 30,000 pounds, according to the firm. Additional information -- including the availability of a new gasoline engine -- will be released in the coming months.

At launch, the line-up will include a number of different configurations ranging from a basic, construction site-spec truck to the luxurious Denali model. The latter comes decked out with leather, wood trim, and dark aluminum accents. GMC will also offer an off-road-focused model named AT4 with a beefier suspension, skid plates, a locking rear differential, and 18-inch alloys wrapped by Michelin all-terrain tires.

GMC is making it easy for Sierra owners to tow a trailer. When properly equipped, the Sierra boasts 15 cameras that let the driver see around the truck; one even "sees" through the trailer. This technology relies on a camera integrated into the tailgate, and a second one that drivers need to install on the back of whatever they're towing. Trailer Sway Control technology, bigger trailering mirrors, and auto grade braking are also available.

Made in Flint, Michigan, the 2020 GMC Sierra Heavy Duty will go on sale later in 2019. Pricing information will be released closer to its on-sale date.

Live photos by Byron Hurd.

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