A slack adjuster free play needs to be adjusted if it is more than about ____ when you pull hard on it.
Answer: A
1 inch
S-cam brakes use slack adjusters to position the pushrod going to the cam. Make sure the parking brake is released and pull each slack adjuster hard while wearing gloves. If it moves more than an inch, the adjuster needs to be tightened.
All choices
- A1 inch
- B1/4 inch
- C1/2 inch
Why the other answers are wrong
B. 1/4 inch
Choice B is wrong because 1/4 inch is too small a free play to require adjustment for manual slack adjusters.
C. 1/2 inch
Choice C is wrong because 1/2 inch free play is less than the maximum allowed 1 inch before adjustment is needed.
CDL Air Brakes Test Info
Questions on Exam
25
Passing Score
80%
Time Limit
Typically 30 minutes; varies by testing location
The Air Brakes test content is federally standardized, so this question applies in every state. Age limits, fees, and testing procedures do vary — check your state's CDL requirements.
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