2025 GMC Sierra 2500HD AT4

Listed by a franchise dealer in Castle Rock, CO · On lot for 54 days · VIN verifiable at NHTSA

This used 2025 GMC Sierra 2500HD AT4 is listed at $66,597 by castle rock ford in Castle Rock, CO 80104. It has 21,699 miles on the odometer (dealer-reported, not independently verified by OAV). The exterior color is White. It features a 4WD drivetrain with a 6.6L V8 engine and Automatic transmission.

OAV's AI-powered Price-to-Market analysis rates this vehicle as a Great Deal — priced below market value. Based on 11 comparable listings matched to this vehicle, the estimated market range is $68,389 to $75,657. These comparisons match year, make, and model and may currently span trims and configurations (trim-level matching is rolling out).

This vehicle has been on the lot for 54 days.

Analysis powered by OAV's patented inventory standardization technology (U.S. Patent No. 12,236,477).

Market context

This listing is part of OAV's broader Castle Rock, CO trucks market analysis. OAV compares vehicles using local and regional price-to-market ranges, days-on-lot, comparable count, and demand signals where available.

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How this deal is rated

OAV compares this 2025 GMC Sierra 2500HD against similar vehicles currently available in the local and regional market — same make, model, and year range (currently across available trims and configurations; trim-level matching is rolling out), filtered for comparable mileage. Based on where this listing falls in that comparable set, it is rated:

• Great Deal — priced below the typical range for comparable vehicles.
• Fair Price — priced within the expected range for comparable vehicles.
• Overpriced — priced above the typical range for comparable vehicles.

Listings show OAV's PTM-derived deal quality and live market context. OAV-claimed dealers manage their listing profile and route buyer inquiries directly. Paid OAV partners surface additional verification signals.

How this listing is verified

This vehicle listing was aggregated from a franchise dealer in Castle Rock, CO, one of 57,000+ U.S. dealerships in OAV's nationwide inventory network.The VIN 1GT4UPEY6SF210325 can be independently verified via the U.S. Department of Transportation's NHTSA VIN decoder, and safety recalls at NHTSA's recall database.

Vehicle attributes (year, make, model, trim, mileage, location) are standardized using OAV's patented methodology (U.S. Patent No. 12,236,477), which normalizes naming conventions and deduplicates cross-listed inventory across the dealership network. Listing data is processed daily; Price-to-Market analysis uses comparable vehicles within the same geographic market.

2025 GMC Sierra 2500HD Market in CO

Based on all 577 2023-2027 GMC Sierra 2500HD listings in the CO market, the average asking price is $79,420. This listing at $66,597 is $12,823 below the broader CO average (16% below the CO average). This is a wider, all-trim comparison across CO; OAV's price verdict above uses the closer comparable set. Comparable prices in CO range from $28,420 to $110,260. Similar vehicles spend an average of 73 days on dealer lots in this market.

Similar GMC Sierra 2500HD Listings in CO

8 similar listings shown (closest matches within ±2 model years) and ±30,000 miles (subject trim: AT4 — compare trims below)