Recently, a concerned consumer in Houston, Texas contacted my law office about a new truck he had recently purchased. He was concerned that his vehicle might be a lemon because he had never been able to obtain the mileage that was shown on the information sticker when he purchased it. He wanted to know if there was any recourse under the state (Texas) lemon laws or fraud statutes because his vehicle appeared to fail to live up to the advertised specifications.
Without determining the strength or validity of any possible legal claims arising from this situation, lets take a few minutes to look at how those fuel efficiency numbers are obtained and why they are there.
The Environmental Protection Agency (EPA), part of the federal government, requires that car manufactures test vehicles to determine their fuel consumption rate. Not every car produced is tested — only a representative vehicle for the specific model. Typically the vehicle tested is a prototype — before production is started. Some very large vehicles (as well as motorcycles) are currently exempt.
Vehicles are tested during simulated driving in a laboratory environment. The car is placed on a dynamometer (rollers under the wheels). The force needed to turn the dynamometer can be varied, thereby simulating different environmental conditions (e.g. headwind, uphill etc). While the car is on the dynamometer, the exhaust from the engine is collected and the amount of carbon emitted is measured. This amount is used to calculate the amount of fuel that is being consumed. The car is “driven” through a series of “courses” that are designed to mimic different types of driving conditions. Examples of the routes can be found at the Fuel Economy site.