2021 GMC Sierra 1500 AT4

Listed by a franchise dealer in Dekalb, IL · On lot for 27 days · VIN verifiable at NHTSA

This used 2021 GMC Sierra 1500 AT4 is listed at $38,371 by brad manning ford inc in Dekalb, IL 60115. It has 70,724 miles on the odometer (dealer-reported, not independently verified by OAV). The exterior color is Black. It features a 4WD drivetrain with a 5.3L V8 engine and Automatic transmission.

OAV's independent, evidence-backed Price-to-Market analysis rates this vehicle as Fair Price — priced in line with the supported comparable range. Based on 28 comparable listings matched to this vehicle, the estimated market range is $25,405 to $45,407. These comparisons match year, make, and model, 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 27 days.

Analysis powered by OAV's patented inventory standardization technology (U.S. Patent No. 12,236,477). Verdict methodology ptm-verdict-v1 · snapshot Sep 2, 2026. The patented comparable band is the input; ptm-verdict-v1 is the versioned OAV rule set that turns it into this verdict.

Market context

This listing is part of OAV's broader Dekalb, IL 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 2021 GMC Sierra 1500 against similar vehicles currently available for sale — 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 comparable-range floor by a meaningful margin (OAV's minimum-gap rule); a listing below the floor by less than that margin is Fair Price.
• 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 Dekalb, IL, one of 57,000+ U.S. dealerships in OAV's nationwide inventory network.The VIN 1GTP9EEDXMZ359256 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.

2021 GMC Sierra 1500 Market in IL

Based on all 442 2019-2023 GMC Sierra 1500 listings in the IL market, the average asking price is $37,771. This listing at $38,371 is $600 above the broader IL average (2% above the IL average). This is a wider, all-trim comparison across IL; OAV's price verdict above uses the closer comparable set. Comparable prices in IL range from $28,227 to $48,664. Similar vehicles spend an average of 64 days on dealer lots in this market.

Similar GMC Sierra 1500 Listings in IL

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

This is a broad, statewide same-model set (any trim, mileage, or title) — not the qualified comparable cohort behind the verdict above; lower prices here typically reflect a different trim, higher mileage, or a branded title.