What Causes a Truck To Jackknife?

Published on Sep 1, 2023 at 2:09 pm in Truck Accidents.
What Causes a Truck To Jackknife?

“Jackknifing” is a common term in the trucking industry. It’s a highly dangerous situation when a truck jackknifes, and it results in far too many crashes every year—many of them fatal.

Federal Motor Carrier Safety Administration (FMCSA) statistics show that in a recent year of study, there were over 2,000 truck crashes in which the first harmful event leading to the collision was a jackknife.

Jackknife accidents are a serious risk that drivers need to consider every time they get behind the wheel of a tractor-trailer. And because a truck jackknife is usually caused by driver error, it is considered to be among the most preventable types of truck accidents.

What Does “Jackknife” Mean in a Truck Accident?

A semi-truck is made up of two main components: the towing vehicle (the truck cab) and the trailer. This type of vehicle is referred to as an “articulated vehicle,” one constructed with a pivot joint that allows for sharper turning.

Jackknifing occurs when these two vehicle components become unaligned, forming a shape like a capital “L,” “V,” or a pocketknife (jackknife) at the pivot point.

This typically happens when the truck brakes suddenly, but the trailer continues moving, pushing against the cab and swinging out at an angle. If “trailer sway” or “trailer swing” starts to occur while the vehicle is in motion, any abrupt braking can throw the semi-truck off balance and send the momentum-propelled trailer swinging into a jackknife formation.

What Are the Most Common Causes of a Tractor-Trailer Jackknife?

The most common cause of a jackknife is improper braking. That may be…

  • Braking sharply on slippery road surfaces,
  • Misusing the truck’s air pressure braking system,
  • Tailgating other vehicles and not leaving enough braking distance,
  • Braking too late after losing control of speed on a downhill,
  • Selecting the wrong gear for the hill grade,
  • Failing to downshift when needed, or
  • Otherwise braking in a manner that shifts cargo, unbalances a truck, or causes trailer swing.

Commercial truck drivers are required by state and federal laws to have the proper training to know how to safely handle braking and stopping, no matter the driving conditions. Acquiring a commercial driver’s license (CDL) has both a written and driving component that tests drivers’ abilities to navigate tricky braking situations. Because of the known dangers of a jackknife, truck operators have to be specifically trained on and practice the right techniques to avoid a jackknife scenario.

A truck driver who is unqualified or undertrained, inexperienced, or simply doesn’t follow safe braking practices is more likely to cause a jackknife. Drunk driving, distracted driving, and driver fatigue are also common factors that can cause a truck operator to make poor braking decisions.

Other factors that can contribute to and cause a truck to jackknife include:

  • Slippery or icy road conditions
  • Defective equipment
  • Mechanical failure
  • Speeding
  • Miscalculating turns
  • Reckless driving

What Should You Do if You Are Involved in a Jackknife Truck Accident?

As a passenger vehicle occupant, there are few things more terrifying than being involved in a serious collision with a large commercial truck. When you’re traveling down the highway at 65 mph, and a truck driver loses control in the adjacent lane, there may be little you can do to avoid becoming caught up in a jackknife crash.

Many of these collisions are critical and require survivors to be transported immediately to the emergency room via ambulance. In the worst cases, those inside the smaller cars involved may not survive the wreck.

Accident victims who are fortunate enough to walk away from the crash scene without debilitating injuries have an opportunity to preserve their safety and legal rights through quick action. If your physical condition allows you to take these steps, we recommend doing so as soon as possible after the crash:

  • Call 911
  • Get to safety, but do not move anyone who appears seriously injured
  • Speak with a police officer upon their arrival
  • Give your version of events in a factual manner without making assumptions of liability
  • Obtain a copy of the police report
  • Have an EMT on the scene examine you for injuries
  • Proceed to the emergency room if advised, otherwise make an appointment for a complete exam with your doctor as soon as you can
  • Take pictures of the accident scene
  • Ask for the contact information of any eyewitnesses
  • Take down the truck driver’s name, contact, employer, insurance, and CDL information
  • Notify your auto insurance company of the crash
  • Have your vehicle examined by a trusted auto mechanic and save the report and bill as evidence
  • Schedule a consultation with a truck accident attorney to learn your legal options

Corban Gunn, Attorney at Law Protects Survivors of Trucking Negligence

Unskilled driving, poor choices, and careless driving behaviors account for the majority of jackknife truck accidents.

If negligent, reckless, or wrongful actions are what caused the truck to jackknife, the at-fault party should, by law, be held accountable for their misconduct.

At Corban Gunn, Attorney at Law, we are not afraid to take on the big motor carriers. Our legal practice defends the rights of victims and makes the trucking industry aware that harmful deeds will always have consequences. Those consequences should not be yours to carry. It is the legal responsibility of the at-fault party to bear financial responsibility for the harm you suffered at their hands.

If you were injured in a jackknife truck accident in Mississippi, we are the law firm with the skill, resources, and passion to win your case.

Contact Corban Gunn, Attorney at Law to set up a case evaluation. Knowledge of your rights and paths to recovery should never come with a cost. We provide 100% free consultations to truck accident victims and families.



If you can’t call us, fill out the form below. Our initial case evaluations for personal injury cases are always free. No strings attached.