A Guide to Trailer Jacks from The Trailer Parts Outlet

A Guide to Trailer Jacks from The Trailer Parts Outlet

When you’re towing safely, you need a good jack. We’ve assembled some information to help you choose the right jack when you’re adding or replacing this part.


Why do I need a Trailer Jack? 


  • The jack lowers and raises the trailer so you can couple and uncouple 
  • It makes your trailer level when it’s not attached to the tow vehicle
  • Lets you load and unload parked trailers

 Trailer Weight Capacity and Height

Trailer jacks have different weights, lengths, and capacities. You should know the length of the jack when it is fully extended and retracted. But the jack also can’t touch the ground when the trailer is in motion. Let’s take a closer look.

  • Know the Height of the Jack
  • If you’re trying to figure out if a jack is right for your trailer, you should know its length retracted and extended. For jacks, it is usually easy to find this. These measurements are taken from the bottom of the jack, and they include the footplate and mounting point. However, mounting points can vary depending on the style of the jack. Pipe mount jacks are measured to the center of the mounting pipe. Standard a-frame jacks are usually measured to the bottom of the mounting flange. Jacks with bolt-on brackets get measured to the centerline. 

  • Know the Trailer Tongue Weight
  • Trailer tongue weight is the weight that the coupler puts on the hitch ball. The Tongue Weight, or TW, is 10 to 15 percent of your gross trailer weight, which is GTW. To use an example, a 5k trailer has a TW of 500 pounds weighing down on the hitch ball. Choose a jack rated for your TW. 

    Note: using a jack that surpasses your TW is ok in many cases! In fact, it may often be a similar price range.  

  • Knowing the Tongue Trailer Height is Important 

  • Checking out a new jack? When the trailer is level and parked, take the height of the ground to the bottom of the trailer coupler with a tape measure. The jack should reach 4 inches higher than the coupler’s level height. You need to be able to lift it over the ball for couplings. Make sure the jack doesn’t drag and has enough coverage 

    Questions About Trailer Jacks? Contact The Trailer Parts Outlet

    We’re happy to help you with any questions you may have about trailer jack measurement. Call us or write us!

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