Rev Up and Rule the Road 2025: JJ Keller Entry Level CDL Driver Test Challenge!

A common cause of trailer jackknife incidents is oversteering or overbraking. When a driver oversteers, they may turn the steering wheel too sharply, which can cause the trailer to swing out and create a loss of control. In a similar fashion, overbraking—especially if the trailer brakes are applied more forcefully than the tractor's brakes—can cause the trailer to pivot around the rear axle of the tractor, leading to a dangerous jackknife situation.

Understanding the dynamics of a combination vehicle is vital for a commercial driver, as the trailer can independently move in response to steering and braking actions of the truck. Maintaining balanced control between the tractor and trailer is essential for preventing such incidents. Consequently, managing speed and making smooth, gradual steering and braking movements are critical to ensuring that the vehicle remains stable and within the intended path, thus avoiding jackknife scenarios.