‘Gross combination weight rating’ means the greater of:

(1) The value specified by the manufacturer of the power unit of a vehicle, if:

(a) The value is displayed on the Federal Motor Vehicle Safety Standards certification label; and

(b) The vehicle is towing another unit; or

(2) The sum of the gross vehicle weight ratings or gross vehicle weights of the power unit and the towed unit, or any combination thereof, that produces the highest value. [1989 c.636 § 4; 2017 c.190 § 9]