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Trailer towing notes

We see vehicles towing trailers during every driving outing.  Passenger vehicles operating “in tandem” have things affixed to their rears ranging from small utility trailers to lengthy homes on wheels and everything else in between.

Many of these towables are infrequently used, sometimes resulting in a lackadaisical approach when owners hook them up.  There are many regulations applying to trailer operation which often go unknown or unheeded.

Certain rules for trailer towing mimic those for semi-trucks, such as those regarding speed limits and lane use.  The speed limit for towers is the same as posted for trucks, which, on freeways, is typically 10 mph lower than the main speed limit.  Additionally, like for all vehicles, the left lane is to be used only for passing, and the far left lane of any highway having three or more lanes provided for travel in the same direction is forbidden for trucks and vehicles with trailers.

I often see small trailers making a trip to the dump or another short run with no operable lighting.  Washington specifies trailer lighting requirements, with several governing laws (RCWs) on the books.  RCW 46.37.050, 060 and 070 specify that every trailer manufactured after January 1, 1964 must be equipped with two tail lamps mounted at the rear, two or more stop lamps, and electric turn signal lamps.  License plate illumination is also required, plus two or more red reflectors.  Additional clearance markers are required for trailers of certain heights and widths.

Safety chains are mandated, connecting the trailer tongue to the towing vehicle’s hitch.  Washington Administrative Code 204-70-070 is specific, reading, in part, “The means of attachment of safety chains shall be located equally distant from and on opposite sides of the longitudinal centerline of the towing vehicle and of the trailer.  Safety chains shall be so connected that the slack for each length of chain between trailer and towing vehicle is the same and is not more than necessary to permit the proper turning of the vehicles.  When passing forward to the towing vehicle, safety chains must be crossed in such a manner as to prevent the tongue from dropping to the ground and to maintain connection in the event of failure of the primary connecting system.”  Besides all of that, breaking force for the chains is specified at 2000, 3500, 5000, and gross trailer weight for Class 1, 2, 3 and 4 hitches respectively.

Hitch classes are rated for gross towing loads as follows:  Class 1, 2000 pounds or less; Class 2, 2001-3500 pounds; Class 3, 3501-5000 pounds; and Class 4, 5001-10000 pounds.

Another RCW, 46.37.500, states, “No person may operate any motor vehicle, trailer, or semitrailer that is not equipped with fenders, covers, flaps, or splash aprons adequate for minimizing the spray or splash of water or mud from the roadway to the rear of the vehicle.” 

Be certain that you are in compliance with legal requirements when towing a trailer.  Also, check vehicle hitch, trailer tongue and trailer frame for absence of breaks, bends, or cracks in welds; there is substantial and continuous strain imposed on these components during travel.  Neglected tires and wheel bearings are responsible for many breakdowns — be sure to check and service them regularly.  And, of course, any trailer operating on the roadways must have up-to-date license plates, registration and title.

Safe, trouble-free trailer use is easy to accomplish if you follow basic regulations.

Readers may contact Bill Love via e-mail at

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