This paper utilizes a wavelet approach to interpret the interaction between truck dynamic axle loads and pavement roughness profile. The experimental data used was obtained from an instrumented 5-axle semi-trailer truck equipped with an air and a rubber suspension in the drive and trailer axles, respectively. Wavelet decomposes the original signal into a number of sub-band levels depending on its characteristics. The size of the dataset used allowed 11 levels of wavelet decomposition with test speed dependent frequencies ranging up to 4 cy/m. For dynamic load, the extent of variation in each of these wavelength sub-bands, was summarized through an energy metric effectively computed as the sum of the squares of the wavelet coefficients in each sub-band. Total energy was computed as the sum of the energy of all sub-bands and was normalized by dividing by the length of the test section. Relative energy was computed as the percent of total energy in each sub-band. The results were summarized through 3D plots of relative energy versus load frequency versus profile frequency. The profile frequencies mostly affecting dynamic loads depend on speed and range from 0.65 to 3.76 cy/m.