What is recommended to use when a trailer begins to sway?

When a trailer begins to sway, steering into the sway is the recommended action. This technique helps stabilize the trailer by allowing it to align more directly with the tow vehicle's path. By turning the steering wheel in the direction of the sway, you counteract the motion and can regain control of the vehicle-trailer combination. This method is effective because it works with the natural forces acting on the trailer rather than against them.

Other actions, such as accelerating, could worsen the sway by increasing speed and momentum, while braking firmly might lead to jackknifing, an instability that is particularly dangerous with trailers. Maintaining a steady speed might not sufficiently address the swaying, as the underlying issue remains uncorrected. Therefore, steering into the sway creates the most responsive and controlled approach to regain stability in such a situation.