When Royal Jones started out driving a truck as an owner-operator in 1981, he averaged 5.5 miles per gallon. The next year, he bought a second truck and hired two drivers who together averaged 4 mpg, but he quickly realized his business was losing money every month.

It was sink-or-swim time for his small business, and Jones knew he could create positive cash flow by focusing on one of the few costs he actually could control – fuel.

He added clutch fans and pulse manifolds on his tractors, set the governors to 68 mph and talked to his drivers about the importance of fuel efficiency. Two months later, both drivers were getting 5.5 mpg, and Jones’ startup finally was turning a profit.Today, Jones has grown that business to become Mesilla Valley Transportation (CCJ Top 250, No. 78), one of the industry’s largest fleets. The Las Cruces, N.M.-based dry van carrier’s name is synonymous with fuel efficiency; the 1,350-truck fleet currently averages 9.01 mpg and only 4 percent idle time.

“We started thinking about fuel efficiency in 1982, trying to do everything we could to shave fuel costs,” remembers Jones, now president and chief executive officer. “The easier you ran the truck, the better fuel mileage you got and the less wear-and-tear you put on the drivetrain.”

Measuring results

With that mindset firmly established, the company soon realized 7 mpg, but only by paying close attention to the numbers. In 1984, after discovering a performance discrepancy of 0.5 mpg between two nearly identical trucks, Jones conducted the first of hundreds of fuel efficiency-related tests over the next 31 years.

The only difference between the two trucks was a slightly longer wheelbase on the second truck, creating an extra 6 inches of gap between the tractor and trailer. On a calm day, Jones took the two trucks to the top of a hill and got them to 60 mph before kicking it into neutral. As they descended the hill for exactly one mile, the first truck accelerated to 63 mph, while the second truck decelerated to 58 mph.

Jones took the second truck back to the shop and slid the fifth wheel up 6 inches and repeated the test. This time, the truck achieved 63 mph after one mile, the same as the first truck, simply by reducing the tractor-trailer gap.

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