Summary

• With 74 currently listed for sale near Worcester, MA and an average price of $51,247.00, 18.9% of 2021 GMC Sierra 3500HDs for sale on CarGurus are rated as good or great deals.

• Favorably reviewed: Owners rated the 2021 GMC Sierra 3500HD 5 / 5 stars.

• 74.3% of 2021 Sierra 3500HD models on CarGurus are accident free.

Why it stands out

The 2021 GMC Sierra 3500HD stands out as a heavy-duty truck that blends serious work capability with a surprisingly broad range of configurations and features. It was offered with a regular cab, an extended cab, or a crew cab, and buyers could pair those body styles with either a 6’10” short bed or an 8’2” long bed, plus either single- or dual-wheel rear axles. Under the hood, it came with a 6.6-liter V8 rated at 401 horsepower and 464 pound-feet of torque, or a 6.6-liter Duramax turbodiesel V8 making 445 hp and 910 lb-ft of torque. Properly equipped, it could haul as much as 7,442 pounds of cargo and tow up to 35,500 pounds, which underscores its appeal to shoppers who need a truck built for demanding jobs.

The 2021 model also offered a wide spread of trims, from the work-focused base model to the luxury-oriented Denali. Even the entry version included a seven-inch infotainment touchscreen, Apple CarPlay and Android Auto, while higher trims added features such as the MultiPro tailgate, trailering assist features, heated front seats, a head-up display, surround-view cameras, and a native navigation system. For 2021, a new jack-knife alert system debuted, the SLE gained the MultiPro tailgate, the Denali added the surround-view camera and a bed-view camera, and the AT4 gained optional mud tires and a side step with extra ground clearance. That mix of towing tech, off-road equipment, and upscale amenities makes the Sierra 3500HD unusually versatile for a truck of this size.

There are a few tradeoffs to keep in mind. Heavy-duty trucks like the Sierra 3500HD are exempt from fuel-economy estimates, but the source notes that you should expect some of the lowest numbers of any non-commercial vehicle. It also points out that later years can be unwieldy in parking lots, and that rivals typically can tow more. Even so, the 2021 Sierra 3500HD remains distinctive for buyers who want a truck that can work hard, offer modern convenience, and still be ordered in a wide range of practical and premium configurations.

Other model years to consider

• 2024 GMC Sierra 3500HD

  • Average price: $71,808.00
  • Good/great deal percentage: 18.8%
  • User rating: 5 / 5
  • Total listings: 149

• 2023 GMC Sierra 3500HD

  • Average price: $67,739.00
  • Good/great deal percentage: 18.3%
  • Total listings: 142

• 2022 GMC Sierra 3500HD

  • Average price: $48,461.00
  • Good/great deal percentage: 22.6%
  • User rating: 4.25 / 5
  • Total listings: 84

This analysis is based on CarGurus' proprietary market data from August 18, 2026, CarGurus experts' opinions, and generative AI.