What It Means
Jackknife crashes are among the most dangerous truck wrecks. A fully loaded commercial truck can weigh 80,000 pounds, and once the trailer swings out, drivers behind it may have no time to stop.
Common causes include:
- Improper brake adjustment and maintenance. Poorly set brakes can make the trailer axles lock before the tractor axles during hard braking, so the trailer swings out.
- High speeds. The faster a truck travels, the more likely the driver is to slam on the brakes in an emergency.
- Sharp curves and evasive maneuvers, especially combined with speed.
- Slippery roads. Any loss of traction can shift a truck’s weight and send both cab and trailer sliding.
- Driver fatigue and inexperience, which slow reactions and make panic more likely.
Why It Matters in a Truck Accident Case
Many of these causes trace back to choices by the driver or the trucking company: speeding, pushing past hours-of-service limits, poor training, or skipped maintenance. Federal rules require motor carriers to “systematically inspect, repair, and maintain” the vehicles they control (49 CFR 396.3).
Proving what happened usually takes evidence such as the truck’s onboard data recorder (speed and brake use), eyewitness statements, the police report, and medical records. Trucking companies and insurers move quickly to build a defense, and legal deadlines apply, so it helps to act promptly.
