Before 1970, the impact of regulations on the cost of transportation and distribution was generally direct, identifiable and relatively minor. Costs consisted mostly of state and federal motor vehicle license, title, and registration fees plus highway use and fuel taxes. By the mid-1970s, things were changing as the National Highway Safety Administration (NHTSA) expanded its original Motor Vehicle Safety Standards-regarding automobile design and manufacture-to include trucks. The MVSS 121 (antilock air brakes) and MVSS 105 (antilock hydraulic brakes) standards were the first to add major costs to the purchase price and operating costs of trucks, truck tractors and semi-trailers.
During the same period, EPA was regulating automotive exhaust emissions, leading to the elimination of lead as a gasoline performance enhancer and automobile average-miles-per-gallon-performance standards for auto manufacturers. Gasoline engine emission reduction requirements resulting in reduced fuel mileage for medium-duty route trucks were partially responsible for the shift to more cost- and energy-efficient diesel-powered delivery fleets.