How To Adjust Automatic Slack Adjusters

Automatic slack adjusters play a crucial role in contemporary braking systems. They are vital in keeping the appropriate distance between brake pads and ensuring the effective functioning of your vehicle’s brakes. Unfortunately, these adjusters can lose their alignment or get damaged as time passes, making it necessary to adjust them to regain their optimal performance.


In this article, we will discuss the importance of automatic slack adjusters and provide a step-by-step guide on how to adjust them. We’ll also cover some common issues that may arise during the process and offer solutions for addressing them.

Understanding Automatic Slack Adjusters

Automatic slack adjusters are self-adjusting mechanisms designed to maintain proper clearance between brake pads and rotors. They work by automatically compensating for wear and tear on the brake system, ensuring that the pads remain in optimal position.

Signs of Misaligned or Damaged Automatic Slack Adjusters

There are several signs that may indicate misaligned or damaged automatic slack adjusters. These include uneven brake pad wear, excessive noise during braking, and a decrease in overall braking performance.

Step-by-Step Guide to Adjusting Automatic Slack Adjusters

  1. Park your vehicle on a flat surface and engage the parking brake. Ensure that the wheels are chocked for added safety.
  2. Locate the automatic slack adjuster, which is typically found near the brake caliper or drum. It may be necessary to remove some components to access it fully.
  3. Inspect the adjuster for any signs of damage or wear. If there are visible issues, consider replacing the component before attempting adjustment.
  4. Using a wrench or socket set, loosen the locknut on the adjuster. This will allow you to make necessary adjustments without damaging the threads.
  5. Turn the adjusting nut clockwise until it reaches its maximum point of travel. You may need to apply some force to overcome any resistance caused by brake pad wear or corrosion.
  6. Once you’ve reached the maximum point, back off the nut slightly (approximately one-quarter turn) to allow for future adjustments as needed.
  7. Tighten the locknut securely using a wrench or socket set. Ensure that it is properly torqued according to manufacturer specifications.
  8. Test your brakes by applying light pressure to the pedal. The pedal should feel firm and responsive, with no excessive travel or sponginess.

Common Issues and Solutions

During the adjustment process, you may encounter a few common issues. Here are some solutions to address them:

  • Stuck Adjuster: If the adjuster won’t move or feels excessively tight, it may be stuck due to corrosion or debris buildup. In this case, try applying penetrating oil and allowing it to sit for a few minutes before attempting adjustment again.
  • Worn Adjuster: If the adjuster feels loose or doesn’t hold its position after being tightened, it may be worn out. In this case, consider replacing the component entirely to ensure proper brake function.
  • Incorrect Torque Specifications: It is crucial to follow manufacturer-recommended torque specifications when tightening locknuts. Using too much or too little torque can lead to issues with the adjuster’s performance and potential damage to other brake system components.


Adjusting automatic slack adjusters is a critical maintenance task for ensuring optimal brake function. By following the step-by-step guide provided in this article and addressing any common issues that may arise, you can effectively maintain your vehicle’s braking system and ensure safe driving conditions.