The purpose of the retarders is to:
Answer: B
Help slow the vehicle while driving and reduce brake wear.
Brake retarders may be of four types; engine, exhaust, hydraulic, or electrical. They are designed to reduce the speed of a vehicle similar to engine braking. This prolongs the life of the service brake components that are applied when the brake pedal is depressed.
Source: Alabama CDL Manual
All choices
- AApply extra braking power to the non-drive axles.
- BHelp slow the vehicle while driving and reduce brake wear.
- CHelp prevent skids.
Why the other answers are wrong
A. Apply extra braking power to the non-drive axles.
Retarders do not apply braking power specifically to non-drive axles but help slow the vehicle generally.
C. Help prevent skids.
Retarders are not designed to prevent skids but to assist in slowing the vehicle and reducing brake wear.
Alabama CDL General Knowledge Test Info
Questions on Exam
50
Passing Score
80%
Time Limit
Typically 60 minutes; varies by testing location
Age Requirements
Intrastate: 18+ · Interstate: 21+
Alabama Law Enforcement Agency (ALEA)
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