The 2015 IMSA Tudor United SportsCar Championship (TUSC) was the second And final season of the International Motor Sports Association's Tudor United SportsCar Championship and last to be held under that name. It was also the 45th overall season of the IMSA GT championship tracing its lineage to the 1971 IMSA season. It began January 24 with the 24 Hours of Daytona. and ended on October 3 at Petit Le Mans.