Gregory A. Erwin (born April 19, 1970) is an American stock car racing crew chief. He has worked as the crew chief for Robby Gordon Motorsports, Roush Fenway Racing, Team Penske, and Wood Brothers Racing at the NASCAR Cup Series, and for Penske in the NASCAR Xfinity Series. Erwin was also the team manager of Team Penske in the Xfinity Series in 2016.