Destined for greatness under the GMC banner, the 2021 GMC Sierra 3500HD proves that a truck can be a powerful workhorse and offer the utmost in luxury at the same time. GMC drivers, it looks like you can have it all. As the heaviest truck in the GMC lineup, the 3500HD earns its place with its impressive capability that offers a maximum towing capacity of 36,000 pounds and a maximum payload of 6,523 pounds. Of course, that’s only the beginning of everything the 3500HD has to offer, with GMC pulling out all the stops and adding innovative trailering technology and much more to their biggest powerhouse yet!
But does the 3500HD live up to the hype? Does it truly raise the standard for heavy-duty trucks across the industry? From its powertrain and capability to its trailering technology and safety features, the 3500HD brings a lot to the road and earns its place among the biggest, toughest, and most capable workhorses in 2021.
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Starting at $37,300, the 2021 Sierra 3500HD packs a powerful punch at a modest price. Drivers have the option between a gasoline or diesel engine, both of which reflect GMC’s promise that the 3500HD is engineered to dominate. The 6.6-liter V8 direct-injection engine does exactly that by delivering 401 horsepower at 5,200 rpm and 464 lb.-ft of torque at 4,000 rpm. While this is impressive, it pales to the power that comes from the 6.6-liter V8 Turbo Diesel, which produces 445 horsepower at 2,800 rpm and a jaw-dropping 910 lb.-ft of torque at 1,600 rpm.
This power is what makes the 3500HD a beast on the road and GMC’s toughest and most powerful truck. In addition to the two powerful engine options, the 3500HD can be optioned with either rear-wheel drive or four-wheel drive and offers the choice between single rear wheel and dual rear wheel configurations. The truck also offers three cab styles and two bed sizes to choose between, allowing you to design the perfect truck for your needs. These configurations make a world of difference when it comes to the 3500HD’s capability.
When equipped with the diesel engine and dual rear wheels, the 3500HD can tow up to 20,000 pounds on a conventional hitch regardless of the box size, cab option, or drive type. When these components change is when we see the real shift in power. With a fifth-wheel or gooseneck hitch, that figure goes up to a staggering 36,000 pounds for the diesel, dual rear wheel, regular cab configuration.
The crew cab option with single rear wheels reduces this capability to a maximum of 21,500 pounds and a payload of 4,135 pounds. However, the 3500HD redeems itself with the crew cab dual rear wheels. This configuration pushes the maximum trailering capacity to 31,400 pounds on a fifth-wheel or gooseneck with a maximum payload of 5,892 pounds.
While the diesel powertrain pushes the 3500HD to its limit when hauling with a hitch, the gasoline engine offers impressive power and an even better payload. With a regular cab, dual rear wheels, and either rear-wheel drive or four-wheel drive, a gas-powered 3500HD can tow up to 16,800 pounds on a conventional hitch. Talk about impressive for a gas-powered truck!
The gasoline engine delivers a maximum capacity of 17,200 pounds with a fifth-wheel or gooseneck hitch, although that is counterintuitively made possible with the regular cab single rear wheel configuration. The dual rear wheel option sees this decrease to 16,800 pounds. However, the dual rear wheel configuration dramatically increases the maximum payload from 4,534 pounds to 7,442 pounds. That impressive figure, made possible by the lighter weight and superior cooling of the gasoline engine, is what makes the gasoline 3500HD well worth considering.
One of the biggest updates to the 2021 GMC lineup is a new suite of trailering technology known as the ProGrade Trailering System. Designed to streamline the trailering experience from initial hitch-up to towing and beyond, the suite features a variety of integrated tools that give the driver further insight and control. This is what sets the 3500HD apart from other heavy-duty trucks on the road.
This available app takes the guesswork out of hauling heavy loads. The app allows drivers to create multiple custom trailer profiles. When this is done, drivers can select the trailer they’re towing and see vital information like trailer tire pressure, light sequence, maintenance reminders, departure checklists, mileage, fuel economy, and so much more. With the app accessible through the Sierra infotainment system, drivers can safely monitor the trailer at the touch of a button!
In addition to the trailering app, the 3500HD offers a suite of trailering features and view enhancements like Jackknife Alert and Rear Trailer View. The Jackknife Alert is especially helpful since it monitors the position of the trailer in relation to the truck. When the front of the trailer gets too close to the rear of the truck, the system alerts the driver with a yellow warning (75% jackknife potential) or a red warning (90% jackknife potential).
GMC also gives drivers more visibility with the available bed view camera, zoom and hitch guidance, rear trailer view, and rear side view enhancements. The bed view features a center-mounted camera in the high-mounted stop lamp that gives drivers a clear view of the cargo bed. GMC took this feature a step further and added a zoom feature and Bed Hitch Guidance to make hooking up to a gooseneck or fifth-wheel easier.
The rear side view enhancements and the rear trailer view ensure drivers have a clear view of the trailer from every angle. The side view feature gives drivers a split view of both the left and right side of the truck and trailer. While this feature isn’t new for 2021, it includes several updates that make it even more useful and intuitive. Similarly, the rear trailer view isn’t new for the 2021 3500HD but has been enhanced to feature guidelines that make it easier for drivers to back the trailer into a parking spot or other area.
GMC realizes that 3500HD drivers spend a lot of time behind the wheel, which is why GMC is committed to offering the latest in connectivity to make driving the 3500HD an even more enjoyable experience. For seamless smartphone integration, the 3500HD comes standard with Apple CarPlay and Android Auto. These tools allow drivers to sync their smartphones with the truck and access apps like music, messages, navigation, and more from the standard center touchscreen display. GMC takes this connectivity a step further by giving drivers the option to add Alexa Built-In, which gives drivers instant, hands-free access to music, navigation, weather, calls, the latest news, and more.
Advanced connectivity features not only make driving the 3500HD more enjoyable, but they also enhance the driver’s safety by allowing the driver to use voice commands to make calls, listen to music, follow navigation, and more. This reflects GMC’s commitment to ensuring every truck is outfitted with the most advanced safety technology available. Of course, this commitment extends beyond the 3500HD’s Alexa Built-In to more advanced safety features like the available Lane Departure Warning that alerts drivers when the truck is drifting from its lane. The 3500HD also offers Front and Rear Park Assist, a Safety Alert Seat, and Teen Driver Technology, all of which are designed to limit the potential for collisions and give drivers more confidence behind the wheel.