Owner notification began may 13, 1997. Owners who take their vehicles to an authorized dealer on an agreed upon service date and do not receive the free remedy within a reasonable time should contact buick at 1-800-521-7300, chevrolet at 1-800-222-1020, pontiac at 1-800-762-2737, or oldsmobile at 1-800-442-6537.also contact the national highway traffic safety administration's auto safety hotline at 1-800-424-9393.