61-9-403. Mufflers -- prevention of noise. (1) Every motor vehicle shall at all times be equipped with a muffler in good working order and in constant operation to prevent excessive or unusual noise and annoying smoke, and no person shall use a muffler cutout, bypass, or similar device upon a motor vehicle on a highway. (2) The engine and power mechanism of every motor vehicle shall be so equipped and adjusted as to prevent the escape of excessive fumes or smoke. History: En. Sec. 143, Ch. 263, L. 1955; R.C.M. 1947, 32-21-146.
Montana Legal Code
§ 61-9-403
Source: https://mca.legmt.gov/bills/mca/title_0610/chapter_0090/part_0040/section_0030/0610-0090-0040-0030.html· Version 2025