Sleek, fuel-saving VN770 leads tour

The Volvo 465 engine features an exhaust pressure governor which allows it to idle at lower rpm.

In these times of expensive diesel, having a fuel-efficient vehicle is more important than ever. Volvo’s VN770, the official tractor for Overdrive‘s 40th Anniversary Voice of the American Trucker Tour, combines the company’s best efforts in aerodynamics and engine design. The VN770 is equipped with the VE465, a 6-cylinder engine that takes its name from its 465-hp rating.

Volvo has tested the VN770 against tractors without aerodynamic design, says Ed Saxman, manager of sales engineering and product information for Volvo. “We’ve noticed a 56-hp difference between tractors,” he says. That means a nonaerodynamic tractor has to work harder to achieve and maintain the same speed as Volvo’s VN770.

“When you’re traveling on level ground, only 200 to 300 hp is used,” Saxman says “But if you figure fuel economy at that power level, we estimate you can save 5 to 8 cents per mile in fuel costs at 75 mph.”

Aerodynamics is important not just on the outside of the truck but under the hood as well. “We improved our cooling arrangement using a fan ring,” says Frank Bio, director of marketing for Volvo Power. “The fan sits within a ring, and the clearance is tight. It’s connected to the shroud of the radiator and can control the outflow of the fan and its cooling ability.”

Because the company makes the chassis and engine, Volvo was able to maximize their integration with the aerodynamic design, giving the engine an advantage over engines that are designed for multiple makes of trucks, Bio says.

Another big concern is idle time, Bio says. “Our exhaust pressure governor allows the engine to idle at lower rpms, which results in lower fuel use at idle.”

Volvo is also exploring engine electronics to achieve better fuel economy. “Our adaptive cruise keeps the truck at a safe distance, front and side,” Bio says. “That helps fuel economy. Our statistics show the longer you stay in cruise, generally, you will see better fuel mileage.”

The VN770 will be equipped with the adaptive cruise system and other safety and communications technology. It will be open for inspection at truck stops around the country during the tour.