PIB TIP: REDUCE AVERAGE SPEED. It’s easy to get into the trap of driving fast. But speed is the main reason for increased fuel consumption and reduced profit. Experts agree that every mile per hour driven over 60 mph reduces fuel economy by one-tenth of a mile per gallon. The Partners in Business program is produced by Overdrive and the consultants at ATBS, the nation’s largest owner-operator business services firm, and is sponsored by Schneider National Inc. and Freightliner Trucks.