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How to Determine Trailer Tongue Length

by Quinn Marshall

You can purchase commercial utility, travel and ATV trailers pre-assembled from private and commercial sellers. However, this option may cost more than building it yourself, or may not be available in the dimensions or weight capacity you need. If you choose to build your own trailer, it is important to correctly measure the tongue length. A trailer tongue that is too long will cause the trailer to sway, while a tongue that is too short may cause problems turning. According to the California Department of Motor Vehicles, a trailer's tongue length should be twice the width of its tires, but no more than 6 inches longer than the distance between the tongue and axle.

Step 1

Place a tape measure at one end of the tire and measure the distance between it and the opposite end of the tire. Write that measurement down on a notepad and write "Tire Width" next to it.

Step 2

Measure the distance between the end of the tongue and the center of the axle. Write that number down on a piece of paper. Add 6 inches to that length. For example, if the distance between the tongue and axle is 40 inches, then adding 6 inches will make the overall length 46 inches.

Enter the "Tire Width" measurement into your calculator and multiple it by "2." This resulting number is the length the trailer's tongue should be unless it is longer than the length of the trailer from tongue to axle plus 6 inches. If that is the case, then the tongue should be the measurement you received by adding 6 inches to the length of the trailer from tongue to axle. For example, if the tire width is 48 inches wide, but the length from tongue to axle is only 46 inches, then your trailer's tongue length should be 46 inches.

Items you will need

  • Tape measure
  • Calculator

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