KANSAS CITY, Kan. A U.S. District Court judge has ruled that a lawsuit, alleging that fuel buyers are being cheated because fuel prices are not adjusted for the impact of temperature on fuel volume, can proceed.

The judge, Kathryn H. Vratil, ruled against oil companies and fuel retailers in the so-called "hot fuel" case. (See Aug. 1 Bus & Motorcoach News.)

The case is a consolidation of dozen of lawsuits filed against the oil companies and fuel retailers by consumers, truckers and others.

The basis of the suits is that because fuel expands as the temperature rises, the oil and fuel companies are profiting on "extra" gallons crated by the expansion.

The plaintiffs want fuel retailers to install pumps that adjust the fuel measure to reflect the actual fuel temperature as it comes out of underground storage tanks.

A U.S. House Committee on Oversight and Government Reform subcommittee study of 2006 data showed that hot fuel nationwide costs consumers an extra $2.3 billion per year.

The oil companies and gas retailers argue that state regulations and industry standards define a gallon of gasoline by volume, not in terms of its energy output. As long as the customer receives 231 cubic inches of fuel, they contend, the customer is getting what they paid for.

The fuel industry also says the cost of installing temperature adjustment equipment would be prohibitive. NATSO, a trade group that represents truck stop operators, has estimated the cost of equipping each pump at between $1,500 and $3,800.

But the plaintiffs point out that the petroleum industry has pushed for using these adjustments in Canada, where the temperature difference favors the consumer rather than the seller.

In denying a motion by the defendants to dismiss the case, Judge Vratil moves the case to the discovery stage.