Engines
Chevy offers the 2021 Chevy Silverado HD with your choice of two different engines, which are both the same for the 2500HD and 3500HD. The base engine is a 6.6-liter V-8 gas engine that produces up to 401 horsepower and 464 lb-ft of torque. It has a very durable cast iron engine block and uses direct injection and variable valve timing to improve overall engine efficiency. The optional engine is a very powerful 6.6-liter Duramax Turbo-Diesel V-8. This utilizes a specialized air induction system and a variable geometry turbocharger to boost overall engine performance. As a result, this Turbo-Diesel provides 445 horsepower and an impressive 910 lb-ft of torque.
Transmission
There are two different transmissions available for the 2021 Chevy Silverado HDs. If you choose to go with the 6.6-liter V-8 gas engine, it will come equipped with a 6-speed automatic transmission. If you opt for the available Duramax Turbo-Diesel, you will have an Allison 10-speed automatic transmission. This will come in handy as the extra gear speeds will provide you with greater control over your truck.
Towing
One of the biggest reasons to buy a heavy-duty truck is its ability to tow the heaviest trailers. In this regard, the 2021 Chevy Silverado HD does not disappoint. This is especially the case when you add a fifth-wheel or gooseneck hitch to your truck. The 2021 Chevy Silverado HD is offered with either rear-wheel drive or four-wheel drive. If your primary concern is trailering, then choosing a Silverado HD with a rear-wheel drivetrain will increase the amount of trailer your truck can tow.
As you will see, the Silverado 3500HD is able to tow heavier loads than the Silverado 2500HD. This is a direct result of the Silverado 3500HD having a greater gross vehicle weight than the Silverado 2500HD. A full 700-pound difference on most comparable trims of the two trucks.
If you choose to equip your Silverado HD truck with the 6.6-liter V-8 gas engine, you will have the ability to tow up to 17,370 pounds. This is the same figure for the Silverado 2500HD and the Silverado 3500HD. If you opt for the Duramax Turbo-Diesel instead, you will see those figures go up as a result of that incredible amount of torque generated by that engine.
The 2021 Chevy Silverado 2500HD with the Duramax Turbo-Diesel can tow an impressive 18,510 pounds. However, the champion in this regard is the Silverado 3500HD with the Duramax Turbo-Diesel that can tow up to 36,000 pounds, one of the highest amounts for any heavy-duty truck available on the market today. So, if you need to tow really heavy trailers, then the 2021 Chevy Silverado HD is the truck for you.
Payload
The other reason to get a heavy-duty truck is its ability to carry cargo in its trailer bed. The 2021 Chevy Silverado HD gives you a choice of a standard bed or a long bed. If you choose the Silverado 2500HD with the Duramax Turbo-Diesel, you can carry up to 3,715 pounds of cargo, while the same truck with the V-8 gas engine can carry up to 3,979 pounds.
The figures go up considerably when you choose the Silverado 3500HD. When equipped with the Duramax Turbo-Diesel, the Silverado 3500HD can carry up to 6,532 pounds in its payload bed. This figure goes up to 7,442 pounds of cargo when the Silverado 3500HD is equipped with the V-8 gas engine.