Heavy-duty vehicle.

(a) A heavy-duty vehicle is any commercial medium- or heavy-duty on-highway vehicle or a work truck, as defined in 49 U.S.C. 32901(a)(7) and (19). For the purpose of this section, heavy-duty vehicles are divided into four regulatory categories as follows: (1) Heavy-duty pickup trucks and vans; (2) Heavy-duty vocational vehicles; (3) Truck tractors with a GVWR above 26,000 pounds; and (4) Heavy-duty trailers. (b) The heavy-duty vehicle classification does not include vehicles excluded as specified in 49 CFR 535.3. [81 FR 74237, Oct. 25, 2016, as amended at 89 FR 52945, June 24, 2024]