Stenhouse began racing in ARCA in 2008 for Roush Fenway Racing. On May 10, 2008, in only his sixth race in a stock car, Stenhouse, Jr. won his first ARCA RE/MAX Series event at the Drive Smart! Buckle Up Kentucky 150 at Kentucky Speedway in Sparta, KY. He had two wins in 21 races and finished fourth in the season ranking as a rookie.