If you substitute a longer mudflap for trailer use, and you recut mounting holes to cinch up the flap and shorten it to a more practical length, don’t forget to trim off the excess you create at the top of the flap.  Once you remount the shortened flap, any material left above the hanger bar (3” to 4” typically) will drag serious wind in the path of the jet of air coming off the tires.  Remember that correcting little things like this really adds up aerodynamically to improve fuel economy at highway speeds.

This entry was posted on Monday, June 29th, 2009 at 6:02 pm and is filed under Trailer Aerodynamics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.