ThorSport Racing is an American professional stock car racing team that currently competes in the NASCAR Craftsman Truck Series. The team was founded in 1996 as SealMaster Racing and is based in Sandusky, Ohio. Owned by Duke Thorson and his wife Rhonda, it currently fields five teams: the No. 13 for Jake Garcia, the No. 66 part-time mainly for Conner Jones, No. 88 for Matt Crafton, the No. 98 for Ty Majeski, and the No. 99 for Ben Rhodes. The team has won five Truck Series championships, three with Crafton, and two with Rhodes. The team is also the longest continually tenured team in the truck series, having fielded at least one truck in every season since 1996.

The NASCAR Craftsman Truck Series is a pickup truck racing series owned and operated by the National Association for Stock Car Auto Racing (NASCAR), and is the only series in NASCAR to race production pickup truck-based stock cars. The series is one of three national divisions of NASCAR, ranking as the third tier behind the second-tier NASCAR Xfinity Series and the top level NASCAR Cup Series.