What is the primary visual indicator of a properly adjusted automatic slack adjuster?

Question: What is the primary visual indicator of a properly adjusted automatic slack adjuster?

Answer options:

• The brake pedal travel is minimal before braking begins. ✅ The pushrod stroke is within manufacturer's specifications when brakes are applied.
• There is no audible air leak from the brake chamber.
• The brake drums are cool to the touch after driving.

Correct answer: The pushrod stroke is within manufacturer's specifications when brakes are applied.

Explanation: While automatic slack adjusters adjust themselves, it's still crucial to inspect their operation during a pre-trip. The primary check is to ensure that the pushrod stroke, when the brakes are fully applied, is within the manufacturer's specified limits (typically not exceeding 20 mm or 3/4 inch).