Clearance and tail lamps — Montana Permit Test

Every bus or truck over 80 inches wide, and every trailer over 3,000 pounds GVW that wide, must have two clearance lamps on the front and two on the rear, one at each side.

Without lamps at its corners, a wide truck at night looks narrower than it is.

If over 80 inches in width, every bus or truck, and every trailer or semi-trailer in excess of 3000 pounds GVW must have on the front and rear two clearance lamps, one at each side.

Clearance lamps on the front or side show amber light, and clearance lamps on the rear show red light.

Matching colors tell a driver at night whether a truck's lights are its front or its back.

Clearance lamps on the front or side of the vehicle shall display an amber light, and clearance lamps mounted on the rear of the vehicle shall display a red light.

All clearance lamps must be visible for 500 feet when required.

A truck's clearance lamps help only if drivers see them in time to judge its width.

All clearance lamps shall be visible for 500 feet when required.

Any vehicle built after January 1, 1956 must have two tail lamps on the rear, except motorcycles, motor-driven cycles, quadricycles and truck tractors.

A car with one tail lamp out can look like a motorcycle, and drivers misjudge its width.

Any vehicle manufactured after January 1, 1956 shall be equipped with two tail lamps mounted on the rear, except motorcycles, motor-driven cycles, quadricycles, and truck tractors.

A bus or truck must have front and rear clearance lamps when it is wider than what?

80 inches. Without lamps at its corners, a wide truck at night looks narrower than it is. Montana Driver Manual, p.16: “If over 80 inches in width, every bus or truck, and every trailer or semi-trailer in excess of 3000 pounds GVW must have on the front and rear two clearance lamps, one at each side.”