Driving SafelyQuestion 49 of 60
What causes a trailer to swing out and jackknife (trailer skid)?
a.The trailer wheels lock up and the trailer slides sideways, often from hard braking or braking in a turn
b.The trailer wheels have too much traction
c.The kingpin is greased
d.The load is too low
Explanation
A trailer jackknife happens when the trailer wheels lock and lose traction, causing the trailer to slide sideways and swing around toward the tractor. Hard braking, braking in a curve, or slippery roads can trigger it. Smooth braking and keeping traction on the trailer wheels help prevent it.
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