Control & OperationQuestion 75 of 120
You are on a slick, snow-covered road descending a grade. What should you do with the engine brake or retarder?
a.Set it to the highest setting for maximum control
b.Turn it off, because a retarder can cause the drive wheels to lose traction and skid on a slippery surface
c.Cycle it on and off every few seconds
d.Use it only in combination with the trailer hand valve
Explanation
Retarders act on the drive wheels, and on ice or packed snow that braking force can break traction and start a jackknife. Higher settings and rapid cycling make the problem worse, and the trailer hand valve should not be used as a speed-control device on a grade.
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