Thermal properties of polymeric materials were measured to identify phase changes and decomposition characteristics as the materials are heated through their decomposition temperatures. Fifty-seven polymeric components used on the 1997 Chevrolet Camaro were studied. Consideration was also given to parts different from those analyzed previously for the Dodge Caravan investigation. The base polymers in these parts were identified by Fourier transform infrared spectroscopy and pyrolysis/gas chromatography/mass spectroscopy. Filler content and type were determined by thermogravimetric analysis (TGA). High-resolution TGA was used to determine thermal decomposition temperatures, and rates of decomposition. These analyses were conducted in nitrogen and air atmospheres. Decomposition temperature and rate of decomposition were found to be a function of the chemical structure of the polymer. For the polymeric materials examined in this study, we observed thermal decomposition temperatures in the range of 270 to 500°C when the samples were heated in air and in the range of 284 to 450°C when the samples were heated in nitrogen. We also used TGA to determine the amounts of organic residues including carbon black, and the amounts of inorganic fillers in the different components. Differential scanning calorimetry (DSC) measurements were conducted using a modulated differential scanning calorimeter. Melting points, glass transition temperatures, heat capacities, heats of fusion, and thermal conductivity values were calculated from the DSC data. These variables measure the amount of heat absorbed or evolved during heating of the sample.