2026 GMC Sierra 2500HD Denali Ultimate

Listed by a franchise dealer in Castle Rock, CO · On lot for 72 days · VIN verifiable at NHTSA

This new 2026 GMC Sierra 2500HD Denali Ultimate is listed at $90,609 by castle rock gmc in Castle Rock, CO 80104. It has 7 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 independent, evidence-backed Price-to-Market analysis rates this vehicle as a Great Deal — priced below market value. Based on 10 comparable listings matched to this vehicle, the estimated market range is $91,044 to $94,579. The local market range in CO is $91,044 to $94,579. These comparisons match year, make, model, and market, using trim where trim data supports it. OAV does not adjust comparables for odometer — where mileage would distort a verdict, it withholds one instead.

This vehicle has been on the lot for 72 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 by local and regional price-to-market ranges and comparable count; days-on-lot and demand signals are shown separately, not as verdict inputs.

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How this deal is rated

OAV compares this 2026 GMC Sierra 2500HD against similar vehicles currently available in the local and regional market — same make, model, and year range, using trim where trim data supports it. OAV does not adjust comparables for odometer; on very high-mileage vehicles it withholds a verdict rather than overstate a discount the odometer explains. 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 can surface additional verification signals, but commercial participation never changes a listing's Price-to-Market verdict, eligibility, ranking, or confidence.

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 1GT4UXEY5TF304892 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.

2026 GMC Sierra 2500HD Market in CO

Based on all 590 2024-2028 GMC Sierra 2500HD listings in the CO market, the average asking price is $80,182. This listing at $90,609 is $10,427 above the broader CO average (13% above 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 $58,661 to $96,965. Similar vehicles spend an average of 74 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: Denali Ultimate — compare trims below)