How do you measure pushrod stroke (applied stroke) when checking brake adjustment?

• A.Mark the pushrod where it leaves the chamber with the brakes released, make a full brake application, and measure how far the mark moved
• B.Measure the length of the slack adjuster arm with the wheels removed
• C.Read the air gauge before and after one pedal application
• D.Measure only the distance from the drum to the lining

Why

The difference between the released mark and the applied position is the stroke the chamber actually used. Comparing that movement with the limit for that chamber size tells you whether the brake is in adjustment.

Manual topic: Air Brakes - Slack Adjusters · From the Air Brakes practice bank (AB-157).

Practice this subject as a full test

More Slack Adjusters & Pushrod Stroke questions

• What does a slack adjuster do in an S-cam air brake?
• For many common brake chambers with a manual slack adjuster, about what pushrod stroke is the commonly cited maximum limit?
• What happens when pushrod stroke becomes excessive?
• When checking slack by hand, how much free movement at the slack adjuster suggests the brake needs adjustment attention?
• With the service brakes fully applied, what angle relationship should the pushrod and slack adjuster arm show?