2020 GMC Sierra 3500HD Review: Heavy-Duty Mega Hauler
When it comes to the heaviest haulers in the full-size truck market in the US, few do it better than the 2020 GMC Sierra 3500HD heavy-duty truck. It is made to haul enormous loads and carry massive payloads, as are rivals like the Chevrolet Silverado 3500HD and the Ford F-350 and F-450 Super Duty. After doing duty in the USA since the nameplate was first introduced in 1988, the Sierra has been redesigned for 2020, with the fifth-generation model sporting an all-new design and improved fuel economy and safety. In terms of its drivetrain, the Sierra 3500HD delivers with a 10-speed automatic transmission and 6.6-liter gasoline V8 with 401 horsepower or an available turbocharged 6.6-liter V8 diesel with 445 hp, so it can do all the heavy lifting demanding owners require. However, competition is strong in this class and its rivals have not been napping, offering mostly better interiors than the GMC. Still, GMC hopes to have a leg up on them with features like the world-first six-function MultiPro tailgate.
Sierra 3500HD Exterior
Dimensions
| Length | Wheelbase | Height | Max Width |
|---|---|---|---|
| 250.1 in | 158.9 in | 80.9 in | 81.9 in |
Sierra 3500HD Performance
Engine and Transmission
This year, the new-for-2020 6.6-liter gas V8 generates 401 hp and 462 lb-ft of torque, paired to a 6-speed automatic transmission. The sole diesel option is a 6.6-liter turbocharged V8 with 445 hp and 910 lb-ft, mated to an Allison 10-speed automatic transmission. 2-wheel-drive and 4-wheel-drive drivetrains are available, as well as single and dual rear wheels. The Sierra 3500HD has a towing capacity of up to 35,500 pounds when equipped with the diesel engine.
Sierra 3500HD Interior
Sierra 3500HD Trunk and Cargo Space
Warranty
| Basic | Drivetrain | Drivetrain Note | Rust-Through | Corrosion | Roadside Assistance | Roadside Assistance Note | Maintenance Note |
|---|---|---|---|---|---|---|---|
| 3 Years / 36,000 Miles | 5 Years / 60,000 Miles | HD Duramax Diesel: 5 Years/100,000 Miles; Qualified Fleet Purchases: 5 Years/100,000 Miles | 6 Years / 100,000 Miles | 3 Years / 36,000 Miles | 5 Years / 60,000 Miles | HD Duramax Diesel: 5 Years/100,000 Miles; Qualified Fleet Purchases: 5 Years/100,000 Miles | 1 Year/1 Visit |
Verdict: Is the 2020 GMC Sierra 3500HD A Good Truck?
Not everybody loves the way the new 2020 GMC Sierra 3500HD pickup truck looks, but ability and reliability are more important in this class than trivialities such as style and here, this heavy hauler delivers, particularly in diesel guise. The new gasoline V8 engine, impressive as it is, can wilt under the heaviest loads at times, whereas the formidable turbo-diesel engine and its great new 10-speed Allison transmission always seem to have an answer. Sadly, the vehicle's interior is less hit and more miss, falling short in terms of design and quality compared to products from Ford and Ram. If you don't mind the subpar cabin - and working hard is all you want to do - the Sierra will certainly meet your expectations, especially the diesel with its mammoth torque and superior gas mileage.
What GMC Sierra 3500HD Model Should I Buy?
You likely wouldn't be reading a review of the 2020 GMC Sierra 3500 HD if you weren't in need of something that can haul big loads. That's why we'd recommend looking at the diesel engine right of the bat to unlock the highest available towing capacity. After that, it really is up to you to choose whether you want a 2-door or 4-door cab, what load bed length you require, and which specification level will strike the best balance of heavy-duty workhorse and comfortable commuter. Given GMCs are technically supposed to be a little more luxurious and are bought by a slightly different clientele to their Chevrolet counterparts, you'll likely want to look at either an SLT, off-road-biased AT4, or the ultra-luxe Denali. However, for the latter, the price of the 2020 GMC Sierra 3500HD truck can easily surpass $70,000.