Used 2021 GMC Sierra 3500HD for Sale near Prince Edward Island

Summary

• With 71 currently listed for sale and an average price of $65,164.00 CAD, 26.8% of 2021 GMC Sierras 3500HD for sale on CarGurus are rated as good or great deals.

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

• 100.0% 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 more polished feel than many buyers expect from a one-ton pickup. It was part of the fifth generation, which debuted as a 2020 model, and that redesign brought a larger footprint, revised styling, and meaningful gains in towing capacity. GMC also offered it in a wide range of cab, bed, and rear-axle configurations, so shoppers could tailor it closely to work needs.

For 2021, the Sierra 3500HD gained a new jack-knife alert system and the MultiPro tailgate. The Denali trim added a surround-view camera and a bed-view camera, while the AT4 gained optional mud tyres and a side step with extra ground clearance. The truck’s available 6.6-litre V8 produced 401 horsepower and 464 pound-feet of torque, while the 6.6-litre Duramax turbodiesel V8 made 445 hp and 910 lb-ft of torque. Properly equipped, it could haul as much as 3,375 kilograms and tow up to 16,100 kilograms, figures that place it firmly among the most capable pickups in its class.

What makes the 2021 Sierra 3500HD appealing is the way it combines that capability with useful technology and upscale trim content. Standard equipment on the base model included a seven-inch infotainment touchscreen, Apple CarPlay and Android Auto, while higher trims added features such as leather upholstery, trailering assist equipment, a Bose premium audio system, and luxury touches like premium leather and parking proximity sensors. The trade-off is that the biggest versions can be unwieldy in parking lots, and top trims can be prohibitively expensive, but for buyers who need maximum towing and hauling with a more refined cabin, the 2021 Sierra 3500HD makes a strong case.

Other model years to consider

• 2024 GMC Sierra 3500HD

  • Average price: $83,272.00 CAD
  • Good/great deal percentage: 25.1%
  • User rating: 5 / 5
  • Total listings: 179

• 2023 GMC Sierra 3500HD

  • Average price: $74,807.00 CAD
  • Good/great deal percentage: 27.0%
  • Total listings: 163

• 2025 GMC Sierra 3500HD

  • Average price: $94,147.00 CAD
  • Good/great deal percentage: 26.8%
  • User rating: 5 / 5
  • Total listings: 153

This analysis is based on CarGurus' proprietary market data from August 10, 2026, CarGurus experts' opinions, and generative AI.