The Technology and Maintenance Council recommends mounting mirrors so that the inner edges are at least 1 inch outboard of the widest portion of the load or cargo box. If they are closer than 1 inch, there will be blind spots.

Visibility is vital to safe driving. About 90% of the input we use to make driving decisions comes through our eyes. If vision is diminished, so is advance warning of potentially dangerous situations.

Truck operators use three vision pathways when driving:

  • Direct: windshields and side glass
  • Indirect: mirrors
  • Electronic: devices that provide awareness of what may be in blind spots.

Read on to learn how to optimize all three pathways for safer driving.

Direct Vision: Keep It Clean

A clean windshield is critical, especially when bugs streak and smear as wipers try to rub away a clear patch of glass. Change wiper blades when they start to streak and keep windshield reservoirs topped off with high-quality washer fluid.

Though more expensive, use glycol-continuing fluid in winter to melt ice and snow; use bug-dissolving fluid in summer to keep windshields from smearing. They're both well worth the investment.

When applied to a clean surface, polymer coatings prevent water from adhering to windshields, side glass, and mirrors. Whether raindrops or snow, the water forms beads that won't distort vision. They blow away at highway speeds.

In winter, ice can jam wiper frames. Use rubber-covered winter blades that keep ice from getting into the mechanism. New frameless blades, available from Michelin and others, have a strip of spring steel molded inside the blade. They flex freely to follow the contours of today's curved windshields.

Defrosting the outside of the windshield and demisting the inside are tasks still best done with the cab heater and defroster system.

Start with the heat control at high when running just the defrosters. Make sure the heater core, ductwork, and air outlets are clean and free of debris. A small dashboard-mounted hardwired or battery-powered fan hastens demisting by circulating defroster air.

Indirect Vision: Size Matters

Federal Motor Vehicle Safety Standard 111 sets minimum requirements for mirrors on heavy trucks. It calls for at least 50 square inches of flat mirror on each side. That could be an 8-inch diameter circular mirror, or a square less than 7½ inches per side. Shortly after World War II, large, vertical, 1636 mirrors were introduced for trucks out West, giving the name, “West Coast mirrors.” Today's West Coast mirrors are 7316, or 112 square inches, which is more than double the federal requirement. In addition, motorized West Coast mirrors keep the rear of a trailer in view when turning and backing. They can be used with straight trucks to allow an area scan before backing up.