Rising Fuel Costs Reshape Used-Car Values in Q3 — With Efficient Models Winning

Fuel prices have become the dominant variable for the American used-car market as it heads into 2027, according to Cox Automotive economists who spoke during an update to the Manheim Used Vehicle Value Index covering the third quarter of 2026. The index closed September at 205.9, a modest 0.6% dip from 207 a year earlier. That may sound small, but it marks the first month of 2026 in which the Manheim Index has landed below its year-earlier reading, and only the second such occurrence in close to two years. Manheim, a wholesale auction house owned by Cox Automotive, builds the index as a seasonally adjusted, mileage- and segment-weighted gauge anchored to January 1997 at a value of 100.

The broader economic backdrop is doing much of the work. AAA reported on Oct. 7 that regular gasoline averaged $4.36 per gallon nationally, an increase of nearly 40% versus the previous year. Diesel, meanwhile, climbed to an all-time high of $6.52 per gallon on Sept. 22. Cox Automotive deputy chief economist Mark Strand tied the trend directly to consumer mood during an online presentation on Oct. 7: “When gas prices rise, sentiment falls, and vice versa.” In a follow-up interview, Strand widened the frame beyond the pump, noting that diesel underpins the movement of virtually all goods — including the transport of vehicles themselves — while home heating oil costs weigh heaviest on households in the Northeast. A single winter’s heating bill there, he suggested, could swell by $1,000 to $2,000, and that region has been among the weakest economically since oil began climbing.

According to Strand, the trajectory of fuel prices over the coming months carries two very different outcomes. Cheaper gasoline would help sustain demand and steady used-vehicle values. But if prices hold at elevated levels or push higher still, consumer confidence — and with it demand — could erode further. That uncertainty, Strand indicated, makes fuel the single largest unknown hanging over used-car pricing into 2027.

High pump prices are already sorting the market into winners and losers, as Jonathan Gregory, Cox Automotive’s senior director of Economic and Industry Insights, explained during the same webinar. Since January, non-electric used vehicles — a bucket that includes conventional gas-electric hybrids — rated at 40 mpg or better have seen wholesale values climb 9.9%. Models in the 35 to 39 mpg range added 3.7% over the same period. Vehicles on the opposite end of the spectrum moved the other way: those returning under 15 mpg lost 15% of their value, while the 15 to 19 mpg group fell 8.8%, collectively dragging the overall Manheim Index downward. “Fuel economy is showing up in wholesale values,” Gregory said. He also stressed that the efficiency premium is not confined to electric vehicles. “The efficiency premium isn’t just an EV story. Hybrids and other high-mileage vehicles are gaining value while the rest of the market depreciates,” he noted. The weakest mileage tiers, he added, remain dominated by full-size pickups and large SUVs — the very segments most exposed to sustained fuel cost pressure.

Taken together, the third-quarter data paints a used-car market being pulled in two directions at once: sustained demand for thrifty, high-mpg vehicles on one side, and accelerating depreciation for gas-thirsty trucks and big SUVs on the other. For dealers and shoppers alike, the practical takeaway from the Manheim update is that fuel economy has reasserted itself as a concrete, measurable force in wholesale pricing — not merely a talking point in marketing materials.