Chastain, a regular in the Cup Series was driving Niece Motorsports’ No. 45 Chevrolet in the race. He contended for the win and finished third but his truck failed post-race inspection.
NASCAR said his truck violated a rule which provided, “The throttle body must be used as supplied by the NT1 engine supplier without modification.”
The team is allowed to appeal but not immediately indicate whether it would.
As a fulltime driver in the Cup series, Chastain did not collect driver points from his finish, but the team will be credited with a last-place finish as far as owner points.