Used 2020 GMC Sierra 3500HD for Sale nearDenver, CO

How much does the 2020 GMC Sierra 3500HD cost?

Prices have softened 9.73% compared to this time last year, making it a favorable time to shop this model year.

There are 526 listings available, which gives you a solid amount of inventory to compare before you buy.

Is the 2020 GMC Sierra 3500HD a good car?

Yes — the 2020 GMC Sierra 3500HD earns a 5/5 user rating, which points to very strong owner satisfaction. Owners consistently praise its impressive performance when pulling heavy loads, its comfortable and well-built feel, and its strong track record compared with competitors. For you, that means it fits especially well if you want a heavy-duty truck that can handle serious towing while still offering modern convenience and a more polished presentation. With 34.4% of listings marked as good or great deals, there is also a meaningful share of attractive pricing in the market.

Is the 2020 GMC Sierra 3500HD reliable?

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

Owner feedback highlights a reliable, dependable, and trouble-free ownership experience, especially for buyers who plan to count on the truck for heavy-duty use over the long term. That kind of response suggests lower day-to-day ownership anxiety if you choose a well-kept example.

What should I look for when buying a used 2020 GMC Sierra 3500HD?

At 72.6% accident-free, a meaningful share of listings has prior incidents — history verification is especially important.

You should start with a vehicle history report so you can confirm accident records, title status, and service history before you get too far into the process. After that, prioritize a thorough pre-purchase inspection, especially on trucks that may have been used for towing or other demanding work. Focus on overall condition, signs of heavy use, and whether the truck’s equipment and wear match the seller’s story.

Is now a good time to buy a used 2020 GMC Sierra 3500HD?

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

• Deal availability: 34.4% of listings are priced as good or great deals.
• Inventory: There are 526 listings available.
• Price trend: Prices have softened 9.73% compared with last year.
• Clean inventory: 72.6% of listings are accident-free.

If you find a listing below $48,611, that's toward the low end of the year-round range and worth acting on quickly.

What is the 2020 GMC Sierra 3500HD's resale value?

The current average of $48,611 sits slightly below last year's $53,848.

That price movement suggests the truck has already given back some value, which can help you as a buyer but may temper what you recover later if you sell. For a future seller, the current market implies you may need to price competitively to stand out, especially if your truck has higher mileage or visible wear. On the other hand, strong demand for capable heavy-duty trucks can still support resale if your example is clean and well maintained.

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 2020 GMC Sierra 3500HD or consider a different year?

If you're weighing the 2020 against nearby model years, here's how to think about it:

Choose the 2020 if:

• 34.4% of listings are priced as good or great deals.
• At 72.6% accident-free, a meaningful share of listings has prior incidents — history verification is especially important.
• Price trend: Prices have softened 9.73% compared with last year.
• Owners rate it 5/5 — a strong satisfaction signal.

The bottom line: If you want the strongest mix of modern capability, owner satisfaction, and current market value, the 2020 is the primary year to target. If your priority is stretching your budget further, you can also compare nearby years and focus on the cleanest, best-priced truck rather than the newest one.

How does the 2020 GMC Sierra 3500HD compare to the 2020 Ford F-350 Super Duty?

These recommendations are based on CarGurus' proprietary market data from November 3, 2026, CarGurus experts' opinions, and generative AI.