After a detailed introduction and towing demo with the 2020 GMC Sierra HD Denali in September, we were ready to experience the big truck in more real-world conditions. While we don’t have much to tow here at Limited Slip Blog, winter in the Northeast does bring challenging conditions and outdoor activities. With a few pairs of skis and snowshoes secured in the bed, we set off for a long weekend ski trip. The road trip and picturesque New England scenery would provide an excellent means to try the big GMC out on the open road.

In the empty parking lot of Citi Field, the Sierra HD’s true size was without context. Once you put the Sierra HD in traffic, however, you realize just how big this truck is. Not necessarily in length or width, unless you extend the towing mirrors, but in sheer height. Standing in front of the truck, an average side adult male won’t be able to see over the hood. This gives the Sierra HD an equivalent rear-view mirror intimidation factor of an 18-wheeler. The towering height has required some clever engineering to make cargo accessibility easy for humans. The bed lift-in height is an inch lower than the previous generation truck. And aAfter a bit of practice with the six-function MultiPro tailgate, we looked like professionals using the full-width step to climb in and out of the bed. There’s also a new set of side steps at the front of the bed in addition to the steps integrated into the rear bumper. When you’re tying down at all four corners, this makes the process much easier. But as we learned shortly before our photo session, this big rig makes spray washing in a tight car-wash bay a damp and frustrating affair. I’m fairly certain I got nearly as wet as the truck did, and I couldn’t even reach the center of the hood when it came time to towel the truck off.

Beneath the hood of the Sierra HD is your choice of an all-new 6.6L gas V8 or the tried and true Duramax 6.6L V8 turbo-diesel. Both engines share an all-new Allison 10-speed automatic transmission. This first-in-class 10-speed gives the Sierra HD plenty of ratios so that it’s always working in an optimal range. In our tester, that helped make use of 445 horsepower and 910 lb-ft torque more readily. Of course we didn’t do any towing in our winter test, but we already know the Sierra HD can tow a GMC Canyon AT4 without breaking a sweat. In  single-digit temperatures, we fitted the included winter front grille cover to help keep engine temperatures in operating range and improve cabin heating. By mid-week, temps had moderated and we stowed it neatly under the second row seats. If it weren’t for the pronounced turbo whine under heavy throttle and massive Duramax logo on the hood, you might not even our tester was a diesel. That was, until you had to fill the tank. We managed to travel 745 miles on a single tank, netting us 17.6mpg. The one telling aspect of every heavy-duty truck cannot hide, however, is the ride quality. Extra stiff springs and shocks meant for towing, plowing, and gooseneck trailering give the Sierra HD a choppy ride over poor road surfaces.

Riding the Sierra HD Denali is as luxurious and a half-ton Sierra or Yukon Denali. The leather-clad and wood-trimmed cabin features a crisp 8-inch touchscreen, 15-inch head-up display, Bose audio system, built-in WiFi, wireless charging, and Apple CarPlay and Android Auto connectivity. There’s also a huge number of cameras and sensors for park assist, lane change alert, blind zone and rear cross traffic monitors, and automatic emergency braking. There’s even GMC’s rear camera mirror, a feature that has come a long way since we first experienced it on the Cadillac CT6. For a class of truck that used to be solely focused on commercial applications, amenities like ventilated seats and a sunroof no longer seem out of place. In a week that brought bitter cold, snow, and rain, there wasn’t a condition that the Sierra HD couldn’t cope with. The auto-engaging four-wheel-drive system dealt with mud, snow, standing water, and ice with relative ease. All the while, we were comfortably warm with heated seats and a heated steering wheel sitting high above it all.

Whether you’re trailering heavy equipment, towing the family camper, or just hauling the family around town, the GMC Sierra HD Denali has what it takes. There’s no compromise between heavy duty mechanicals or the technology and comfort the Denali brand represents. The only requirement, it would seem, is that it takes an enormous amount of space to package the two together. The new 2020 GMC Sierra HD Denali is bigger, smarter, and more capable than ever before.

-Christopher Little

Related: Tow Like a Pro: 2020 GMC Sierra HD