2020 GMC Sierra Heavy Duty Is Their ‘Most Capable’ Truck Ever
First photos and specs of GMC’s musclebound new truck.
![gmc sierra heavy duty truck](https://www.maxim.com/cdn-cgi/image/quality=80,format=auto,onerror=redirect,metadata=none/wp-content/uploads/2021/05/gmc-sierra-heavy-duty-truck.jpg?resize=788,444)
GMC’s latest Sierra Heavy Duty is here, and it’s already being called the company’s “most capable” truck ever.
The 2020 Sierra HD still runs a 445-horsepower, 6.6-liter Duramax turbodiesel V8. But the high-end pickup now has a brand new Allison 10-speed automatic transmission to handle all 910 pound-feet of torque.
![2020-GMC-Sierra-3500HD-Denali-001](https://www.maxim.com/wp-content/uploads/2021/05/2020-gmc-sierra-3500hd-denali-001-scaled.jpg)
This improved powertrain translates to a towing capacity that GMC says is “well in excess of 30,000 pounds”—official figures have yet to be released.
![2020-GMC-SierraHD-034](https://www.maxim.com/wp-content/uploads/2021/05/2020-gmc-sierrahd-034.jpg)
With a slightly smaller engine, the Sierra HD will probably approach—but not surpass—the performance of the 1000-pound-feet club’s first member: the 2019 RAM HD. But there are other impressive features that might pull truck-lovers over to camp GMC.
![2020-GMC-Sierra-3500HD-Denali-002](https://www.maxim.com/wp-content/uploads/2021/05/2020-gmc-sierra-3500hd-denali-002-scaled.jpg)
The new triple-tiered grille, complementary hood scoop and chrome accents look undeniably badass. It also has a 15-angle camera configuration that allows drivers to “see through” trailing cargo.
Then there’s the nifty “MutliPro” tailgate. The Drive has further details:
For the 2020 Sierra HD, the admittedly-clever piece of kit will be standard on SLT trucks and above and optional on lower trims.
More important to daily users might be the one-inch-lower bed floor that makes load-in and fifth-wheel hitching just a little easier and standard side steps in front of the rear wheels to improve bed access all around.
![2020-GMC-Sierra-3500HD-Denali-003](https://www.maxim.com/wp-content/uploads/2021/05/2020-gmc-sierra-3500hd-denali-003.jpg)
Two trim options will be offered. One is the expected “Denali” package, which upgrades the interior with premium leather-appointed seating, authentic open-pore wood and dark-finish aluminum decor.
![2020-GMC-Sierra-2500HD-Denali-009](https://www.maxim.com/wp-content/uploads/2021/05/2020-gmc-sierra-2500hd-denali-009.jpg)
But the new off-road spec “AT4” trim goes beyond the cabin, with Rancho shocks, skid plates, and 18-inch (or available 20-inch) wheels, plus an “Off-Road” driving mode and inclinometer.
![2020-GMC-Sierra-2500HD-AT4-011](https://www.maxim.com/wp-content/uploads/2021/05/2020-gmc-sierra-2500hd-at4-011-scaled.jpg)
The 2020 Sierra HD’s price has yet to be announced, but those details will come when it hits dealerships this summer.