Resilient Modulus (M r ) is an important material property for pavement design and evaluation. The M r values can be estimated in the laboratory by measuring material's response under simulated field loading conditions. It can also be determined from nondestructive tests such as the falling weight deflectometer. Some previous studies have shown, however, that the M r values determined from laboratory testing can differ significantly from that determined from the backcalculated resilient moduli using FWD data. This paper presents the results of a site-specific comparison of the M r values determined through laboratory testing and backcalculation of FWD data. Both laboratory and FWD data are related to an instrumented pavement section on I-35 in central Oklahoma. Unlike most previous studies that focused on FWD testing on the top of asphalt concrete, in the present study FWD tests are conducted on different layers namely, natural subgrade, stabilized subgrade, aggregate base and asphalt concrete. The study indicated increase in backcalculated M r values due to the construction of overlying layers. For natural subgrade and aggregate base layer, backcalculated M r values were found higher than corresponding laboratory determined M r values. In addition, FWD tests were also performed on top of the asphalt strain gauges and earth pressure cells and strains and pressure data were collected simultaneously. A comparison of the pavement response between the predictions from a multilayer elastic program, KENPAVE, and the in-situ sensors was made.