This report details the activities and process by which the re-backcalculation of LTPP General Pavement Study (GPS) test sections were completed. These activities were completed under FHW A Contract DTFH61-95-C-00029 as part of Task B - "Backcalculate Resilient Modulus". This report details how the backcalculation program was selected, lists the GPS sections re-backcalculated, presents the results of the revised backcalculations and discusses the problem sections that were encountered. The report is also accompanied by a data base that contains results from the original SHRP backcalculation process and those sections that were re-backcalculated.