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Zorluk: OrtaMountain Driving and Steep Downgrades

Engaging an auxiliary retarder while descending a steep mountain grade on wet or icy pavement enhances vehicle stability by distributing braking force across all vehicle axles.

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False. Retarders apply braking torque solely to drive wheels and should be disengaged on slippery downgrades to prevent loss of traction.
The statement is false because auxiliary retarders (including engine brakes, exhaust brakes, and hydraulic or electric driveline retarders) apply slowing force exclusively to the drive wheels. On steep downgrades where the road surface is wet, icy, or snow-covered, this concentrated retarding torque can easily overcome tire traction, causing the drive wheels to lock or slide and precipitating a dangerous jackknife. Commercial drivers must turn off retarders whenever road conditions are slippery.

Adım Adım Çözüm

1
Identify the mechanical operating principle of auxiliary vehicle retarders.
Retarders generate braking torque on the drive axles only, rather than distributing friction braking evenly across all axles.
Understanding where braking forces are concentrated is necessary to assess vehicle directional control.
2
Analyze the dynamics of drive-axle drag on low-traction mountain downgrades.
On wet, icy, or snow-covered pavement, the retarding force on drive wheels can exceed available tire grip, leading to wheel slip.
Commercial driving safety standards require drivers to turn off retarders when roads are slick to prevent drive-wheel lockup.
3
Evaluate the accuracy of the claim presented in the stem.
The claim is incorrect because retarders do not distribute braking to all axles and decrease rather than enhance stability on slick roads.
Confirming the contradiction with standard CDL mountain driving procedures establishes that the statement is false.

Anahtar Kavram

Retarder operation and drive-wheel traction risks on slick mountain downgrades
Tahmini Süre:1m 0s
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Konular

Mountain Driving and Steep Downgrades

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