This paper due to determine an aerodynamic drag for different ways of tarpaulin fixation, specifically tarpaulin tension and disposition on platform-type body of a HDV. More positions of the tarpaulin were investigated. Determination of the resistances was done by coast down test of the vehicle according to Slovakian technical standard (STN). The aerodynamic drag was calculated from actual vehicle deceleration during the coast down test from the actual velocity changes. The vehicle actual velocity was measured by GPS logging device. Results are values of resistance, which affect the vehicle and their sum represents the actual engine power needed for vehicles driving.