• Semi truck owners can decrease fuel expenses with trailer skirts.Semi image by Andrew Breeden from Fotolia.com
  
  Fuel efficiency is important, especially when fuel is a major business expense. Trucking companies face large fuel bills and have had to raise rates to meet the rising cost of fuel. However, trailer skirts that attach to the bottom, front and side of semi-truck box trailers can help to reduce fuel costs by decreasing the drag created as the truck and trailer move down the road.
  
  

Side Skirts

• Side skirts are installed along the bottom of a semi box trailer. These skirts are designed to cut down on the amount of air that passes under the trailer and over the rear axle. By reducing this air flow, the fuel efficiency of the truck is improved. Trailer side skirts are made of both aluminum and fiberglass. The truck's route will determine which material is the best choice for the side skirts. If driving regularly along the coast, fiberglass is the better choice to prevent rusting. However, if traveling along stretches of gravel highway, a metal side skirt is a better, more durable, choice.
  
  

Gap Fairings

• The space behind the cab of the truck and the front of the trailer can create a significant amount of drag as wind passes by the cab and gets trapped in front of the trailer. By installing gap fairings, which fill the space between the back of the truck cab and skirt the front of the trailer, this drag can be reduced, the truck becomes more aerodynamic and the fuel cost of driving the truck is reduced.
  
  

Boat Tails

• A boat tail installed on the back of a box trailer reduces the suction created as wind moves over the top and sides of the trailer and falls off the back. This suction can create drag on the back of the trailer, which reduces fuel efficiency. A boat tail creates a more aerodynamic end to the trailer and allows the swirling air to be diverted away from the back end of the box trailer. The result is reduced suction.