Proposal to introduce optional calculation method for determining f₀ and f₂ road load coefficients, allow measurement of drivetrain delta on component dynamometer, permit evaluation of split runs to increase data base, and enable test vehicle configuration using interpolation method. The calculation method determines final f₀ and f₂ values considering theoretical delta between coast down vehicle and final vehicle. Component dynamometer measurement increases accuracy because not all combinations of road load relevant components can be assembled, allowing all component combinations to be evaluated independently.