FAQ - How Do I Adjust Air Brakes On My Semi-Trailer?

Since your trailer’s air brakes are incredibly important mechanisms in order to properly operate your trailer, it’s important to routinely service them. Even by spending a small amount of time checking on your truck’s air brakes will allow you to find issues, big or small, that could end up costing more money down the road.

To adjust your brakes, here are the basics:

  • Block the wheels of your trailer and truck
  • Climb under the trailer to check for the slack adjusting device and fasten the bolt tightly with a wrench
  • Check the movement of the s-cam and the brake shoes to view their movement toward the brake drum
  • Relax the bolt and check the trailer movement. Make sure to relax the bolt to the point where you keep it from dragging.
  • Check the length of your stroke indicator to make sure that it reads 2” if your chamber size is 30.

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