Inflated MPG Claim Recruiting

EPA Inflated Hybrid Mileage
Plaintiff Recruitment
A Google AdWords text ad was spotted on an automotive site for Brennan, Weiner and Simons, a firm that is pursuing legal action against hybrid car manufacturers for false advertising.

There has been a lot said about EPA testing and its mileage measurement being greater than real life results. As a result, we will soon add mileage data from GreenHybrid's Real Hybrid Mileage Database to our mileage calculator.

Posted on July 24, 2004 | 2 Comments
Jason Siegel's review, dated November 7 '04:

Hello! My name is Jason Siegel, creator of GreenHybrid and the Real Hybrid Mileage Database you speak of. Feel free to use our figures (with reference) and compare to the EPA estimates. Remember, however, that car manufacturers are required by law to use the EPA fuel economy figures in their advertising... and even if they could publish lower numbers, would you really expect them to? :) The advertiser's efforts are likely futile, despite the effort.

Ari Ofsevit's review, dated November 24 '05:

No car gets advertized fuel mileage. The EPA tests are based on tests done indoors, at 68 degrees, in a completely controlled, with NO WIND RESISTANCE because they are conducted on dynamometers — essentially an exercise bike for cars. The test can be used comparitively very well because it is so well controlled, but the numbers produced are generally 10-25% too high. Highway mileage is calculated assuming an average speed of 48 and most driving in the low 50s, when engines are most efficient. Most people drive in the 60s and 70s when wind resistance is much higher (based on the square of the speed of the wind, so there is twice as much resistance at 70 than at 50). If you drive a Prius under optimal conditions: flat road, smooth pavement, no AC, temperature around 70 F, you can attain the published mileage (I have). However, it is generally impractical to drive in these conditions. Cold weather, especially on short trips, greatly diminishes fuel economy as the engine must warm up which uses a lot of gas in the first few minutes of driving.

There is no reason for a class-action lawsuit — the car companies only advertize what the EPA tested. There is no attempt to mislead the consumer, except by the EPA.

Information on how the EPA test is conducted can be found at, and pictures of a test can be found at The EPA notes that fast acceleration and heavy braking can reduce mileage 5-33% and air conditioning can reduce mileage 5-25%. A 1980s study found that drivers were not attaining the published fuel standards and they now adjust them downwards, 10% for city and 22% for highway. Probably, they should redo this study and adjust their estimates down further. Still in all, they are estimates, nothing more, nothing less.

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