Knowledge of the loads and deformations experienced by a tire under operational conditions is essential for the design and testing of tires. Increasing use of analytical stress analysis in the tire design process requires more detailed information on boundary conditions. Increasing use of indoor testing to predict tire endurance makes it necessary to aquire a great deal of information on the magnitudes and distributions of service loads and tire deformations. A technique is described for instrumenting a vehicle's suspension in order to obtain tire loads under operational conditions. Two transducers are also discussed which were developed to measure tire surface strains and tire crown displacements. Tire loads, surface strains, and crown displacements are presented for various track courses and compared with those that can be reproduced on standard indoor test equipment.