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Difficulty: MediumWinter Driving, Snow, and Black Ice

Downshifting to a lower gear to slow down abruptly on an ice-covered roadway is an effective safety technique because engine braking cannot cause drive-wheel traction loss.

Answer: Answer

Answer

False. Downshifting abruptly on an ice-covered road transfers engine drag to the drive wheels, which can break traction and cause a skid.
Downshifting abruptly forces the drive wheels to slow down suddenly due to engine drag. On ice or snow, this sudden shift in wheel speed can easily break tire traction, leading to an immediate skid or spin.

Step-by-Step Solution

1
Analyze the mechanical force produced by engine downshifting.
Downshifting rapidly increases engine drag on the drive axle.
Lower gears force the drive wheels to rotate at lower relative speeds compared to vehicle momentum.
2
Evaluate tire traction on black ice and packed snow.
Ice provides extremely low surface friction between tires and the road.
Sudden changes in wheel rotation force can easily exceed the minimal available traction.
3
Determine the safety outcome of abrupt engine braking on ice.
Drive wheels lose traction, potentially causing the rear or front of the vehicle to slide out.
Safe winter driving requires smooth, gradual deceleration rather than sudden engine or pedal braking.

Key Concept

Drive-wheel traction loss from sudden engine braking on ice
Estimated Time:45s
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Topics

Winter Driving, Snow, and Black Ice

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