EPA seeks real-world tests of mileage claims

By Nora Naughton, Crain News Service

WASHINGTON (July 15, 2014) — The Environmental Protection Agency (EPA) wants to put auto makers' mileage claims to the test.

An EPA proposal would require auto makers to road test vehicles to verify mileage claims posted on window sticker prices, The Wall Street Journal reported, citing EPA officials.

The move follows the recent restatement of EPA ratings on several cars and light trucks by Hyundai, Kia and Ford.

It's part of a broader effort by the agency to more carefully scrutinize mpg figures published by auto makers.

The difference between a driver's actual mileage and what a vehicle is rated is among the most frequent consumer complaints and questions posed to the agency.

“Some auto makers already do this, but we are establishing a regulatory requirement for all auto makers,” Chris Grundler, director of the EPA's Office of Transportation and Air Quality, told The Journal.

The proposal also would make it difficult for auto makers to manipulate lab results to deliver higher mileage claims, the newspaper said.

Ford Motor Co. amended mileage estimates on several hybrids last month, while Hyundai is being sued by consumers in South Korea over accusations it overstated the fuel efficiency of the Santa Fe crossover.

In 2012, Hyundai and affiliate Kia apologized and compensated owners for overstating mileage estimates on light-vehicle models sold in the U.S.

At Ford, the recent mileage claims were based on poor testing conditions and faulty engineering practices, including wind tunnel and other laboratory measurements.

The EPA, as The Journal noted, does not evaluate every new light-vehicle to verify mileage claims. Most fuel economy tests are performed by auto makers, and the information is later shared with and reviewed by the agency.

The data is also published on the agency's public website.

The EPA last adjusted fuel efficiency testing in 2008, which narrowed the gap between window sticker numbers and what owners experienced in real-world driving.

The proposed road test would make real-world driving trials more rigorous and reflect air resistance and rolling friction on a test track rather than in a test lab, The Journal reported.

These factors can affect fuel economy considerably, especially in hybrids.

This report appeared on the website of Automotive News, a Detroit-based sister publication of Tire Business.