Michigan CDL - Air Brakes Practice Exam

If slack adjusters move more than one inch when pulled, what does that indicate?

1. The brakes are functioning properly

2. They may be out of adjustment

3. They need lubrication

4. The system may have air leaks

The correct answer is: They may be out of adjustment

When slack adjusters move more than one inch when pulled, it indicates that they may be out of adjustment. Slack adjusters are critical components in the air brake system that help maintain the appropriate distance between the brake shoes and the drum. If the adjusters are moving more than one inch, it suggests that they are not properly adjusted, which can lead to brake performance issues. Proper adjustment of slack adjusters is vital for ensuring that brakes engage and release at the right times. When they are not functioning as intended due to poor adjustment, it can significantly impact braking power and safety. This situation necessitates a close inspection and potential adjustment of the slack adjusters to ensure that the air brake system operates effectively. Understanding the condition of slack adjusters is key for maintaining safe braking capabilities, making it crucial for drivers and technicians to regularly check and adjust them as needed.