What does "trailer sway" refer to?

"Trailer sway" refers to the uncontrolled side-to-side movement of the trailer while driving. This phenomenon is particularly concerning because it can affect the stability of the entire rig, potentially leading to loss of control. Sway can be caused by several factors, including wind, uneven loading, or abrupt steering inputs. Understanding how to recognize and mitigate trailer sway is crucial for safe driving with a tractor-trailer, as it can lead to dangerous situations like jackknifing or overturning if not properly managed.

The other choices do not accurately define trailer sway; the constant movement referred to in the first option describes another type of instability, while the ability to maneuver in tight spaces is unrelated to sway. Lastly, noise from the trailer during motion does not indicate its stability or control, making it irrelevant to the concept of sway.