The trucking industry is preparing for a new set of Environmental Protection Agency rules that will require much better fuel efficiency from heavy-duty trucks

The EPA is expected to propose new regulations this week aimed lowering greenhouse gas emissions from big trucks. The agency is setting a goal of increasing fuel economy up to 40 percent by 2027, compared to 2010 levels, according to officials interviewed by the New York Times.

Tractor-trailers average about five to six miles per gallon of diesel. The proposed regulations would set the average up to nine miles per gallon.

The EPA says heavy trucks make up four percent of traffic in the U.S., but account for a quarter of greenhouse gas emissions from all vehicles.

Big Truck Fuel Efficiency

It will take some time for the proposed rules to be officially put on the books. A public comment period will begin after the EPA’s announcement, and the rules could face some stiff opposition from industry players who believe they will put too much of a burden on heavy-truck manufacturers.

Experts estimate the new rules could add $12,000 to $14,000 to the cost of a new tractor trailer. The EPA says those extra costs could be recovered through fuel cost savings.

As the proposed rules head down the path for approval, heavy-duty truck manufacturers and operators continue to focus on engineering and other strategies to improve fuel economy and lower greenhouse gas emissions.

Some approaches include improvements to engines and transmissions, the recycling of engine heat to secondary turbines, using lighter materials and boosting the aerodynamics of big trucks.

In an interview with the Times, John Yandell, Jr., president of Yandell Truckaway of Pleasant Hill, Calif., said he was skeptical that 9 to 10 mpg could be achieved in a reasonable time at a reasonable cost.

“Talk is cheap,” Yandell said. “But I don’t see how they get there.”