Retarders:
Answer: A
Can cause the drive wheels to skid when they have poor traction.
Retarders require good traction in order to operate correctly. If weather conditions result in wheel slippage due to poor traction, turn off the retarder until conditions improve.
All choices
- ACan cause the drive wheels to skid when they have poor traction.
- BWork when you apply the brake pedal.
- CCause extra brake wear.
Why the other answers are wrong
B. Work when you apply the brake pedal.
Retarders work independently of the brake pedal and do not activate when the brake pedal is applied.
C. Cause extra brake wear.
Retarders reduce brake wear rather than cause extra brake wear.
CDL General Knowledge Test Info
Questions on Exam
50
Passing Score
80%
Time Limit
Typically 60 minutes; varies by testing location
The General Knowledge 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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