Montana Code Annotated · § 61-10-103 — Height

(1) Except as provided in subsection (2), a vehicle, unladen or with load, may not exceed a height of 14 feet.

(2) Subsection (1) does not apply to an implement of husbandry or a vehicle, unladen or with load, that does not exceed a height of 15 feet 6 inches if:

(a) the implement of husbandry or vehicle is transporting hay, straw, or both for a distance not more than 25 miles and is incidental to farming operations; and

(b) the implement of husbandry or the vehicle will not encounter overhead obstacles 17 feet from the ground or lower while in transit.