Our previously reported steady-state thermal analysis for a rolling passenger tire has been modified. This makes possible a nonsteady-state thermal analysis for tires which operate under nonsteady-state conditions. A finite element analysis was used which involved the solution of a set of simultaneous heat balance equations. Conduction within the tire, conduction to the road surface, convection to the contained air and to the surrounding air, and radiation from the outside and inside surfaces of the tire were taken into account. The experimentally measured infrared surface temperature distribution was used as input data. A new, fast-response infrared camera and infrared recorder were used to obtain the data. The results gave, as a function of time, the complete temperature distribution and rates of heat generation in the tire.