Used 2021 GMC Sierra 3500HD for Sale near British Columbia

How much does the 2021 GMC Sierra 3500HD cost?

Prices have softened 13.20% compared to this time last year, making it a favourable time to shop this model year.

There are 86 listings available, which suggests a modest amount of inventory for this heavy-duty truck.

Is the 2021 GMC Sierra 3500HD a good car?

Yes — the 5/5 user rating points to strong owner satisfaction, and the 2021 GMC Sierra 3500HD’s overview backs that up with its mix of serious work capability and a more polished feel than many buyers might expect. It offers broad configuration flexibility, so you can shop for anything from a basic work truck to a more upscale, feature-rich setup. For buyers who need genuine heavy-duty strength, its towing and hauling capability is a major part of the appeal. The market also shows 27.9% of listings as good or great deals, which gives you some room to shop selectively.

Is the 2021 GMC Sierra 3500HD reliable?

Owners rate it 5/5, a strong signal of long-term satisfaction.

The overview describes a truck built around serious capability, broad configuration choice, and meaningful towing-focused improvements, which are all encouraging signs for used buyers who want a hard-working pickup. Its more polished feel and available technology also suggest a well-rounded ownership experience for the segment. For long-term ownership, the main risk is that a heavy-duty truck like this may have been used for demanding work, so condition and maintenance history matter a lot.

Is now a good time to buy a used 2021 GMC Sierra 3500HD?

This looks like a moderate, selective buyer’s market, so you can shop patiently and still find worthwhile listings.

• Deal availability: 27.9% of listings are priced as good or great deals.
• Inventory: There are 86 listings available.
• Price trend: Prices have softened 13.20% compared with last year.

If you find a listing below $62,072 CAD, that's toward the low end of the year-round range and worth acting on quickly.

What is the 2021 GMC Sierra 3500HD's resale value?

The current average of $62,832 CAD sits slightly below last year's $72,387 CAD.

That price movement suggests the market has already adjusted downward, which can make the truck more attractive to buyers now but may also limit upside for a future seller if prices stay soft. Because this is a heavy-duty truck with strong capability and a broad configuration range, demand should remain tied to how well a specific example fits work or towing needs. If you buy carefully and keep mileage and condition in check, you can help protect value when it’s time to sell.

Vehicles with strong owner satisfaction ratings, like this model year's 5/5, tend to retain buyer demand, which supports resale value over time.

Should I buy a 2021 GMC Sierra 3500HD or consider a different year?

If you're weighing the 2021 against nearby model years, here's how to think about it:

Choose the 2021 if:

• 27.9% of listings are priced as good or great deals.
• Price trend: Prices have softened 13.20% compared with last year.
• Owners rate it 5/5 — a strong satisfaction signal.

The bottom line: The 2021 is the better pick if you want a heavy-duty truck with strong capability, a polished feel, and a market that currently gives you some negotiating room. If you’re especially price-sensitive, a nearby model year may be worth comparing, but the 2021 stands out as a balanced choice for shoppers who want capability first and value second.

These recommendations are based on CarGurus' proprietary market data from October 6, 2026, CarGurus experts' opinions, and generative AI.