Michael Pines | December 18, 2025 | Truck Accidents
When you hear the phrase “jackknife accident,” you might picture a folding pocketknife snapping shut. That image is not far off. In a jackknife truck crash, a large truck suddenly folds at the joint between its cab and trailer, often with devastating results.
For people injured in such wrecks in San Diego, CA, understanding what a jackknife accident is, why it happens, and who may be responsible can make a big difference in pursuing justice and compensation.
What is a Jackknife Truck Accident?
A jackknife truck accident occurs when a tractor-trailer or semi-truck loses control and the trailer swings sideways toward the cab, forming a sharp angle similar to a folding knife. This sudden movement can cause the driver to lose control entirely, sending the truck sliding, spinning, or blocking multiple lanes of traffic.
Because the cab and trailer remain connected, the vehicle may continue moving unpredictably across the roadway. Other motorists often have little to no warning before impact, which can lead to catastrophic outcomes, including severe injuries, multi-vehicle collisions, and, in some cases, fatalities.
How Do Jackknife Accidents Happen in San Diego?
Jackknife crashes are rarely caused by just one issue. More often, several factors come together to create a dangerous situation. In San Diego, where major freeways like I‑5, I‑805, and I‑8 carry heavy truck traffic, the risk becomes serious.
Some of the common causes of accidents include:
- Sudden or improper braking: If a truck driver slams on the brakes, especially on slippery or wet roads, the trailer may keep moving forward while the cab slows, causing the trailer to swing out.
- Poor road or weather conditions: Rain, oil spills, slick surfaces, or road debris can reduce traction. When a heavy trailer is involved, even a small skid can trigger a jackknife.
- Overloaded or improperly secured cargo: If cargo is not evenly distributed or is loosely secured, it can shift during travel. That shifting weight destabilizes the trailer, especially in turns or during braking.
- Excessive speed or reckless driving: Large trucks need much more time and space to stop compared with passenger cars. When drivers speed or make abrupt maneuvers, the risk of jackknifing goes up.
- Driver fatigue, inexperience, or distraction: Long hours behind the wheel, lack of training, or distractions such as phone use cause delayed reactions or poor decisions.
- Mechanical failures: Problems such as brake failure, worn tires, or faulty trailer-cab connections can lead to loss of control.
Because the causes are often interrelated, many jackknife accidents result from several issues working together.
Why Jackknife Accidents Are Especially Dangerous
Jackknife accidents are among the most hazardous types of truck crashes due to the size, weight, and unpredictability of the vehicles involved. Several factors make these collisions particularly dangerous, including:
- Blocked roadways: When a semi-truck jackknifes, the trailer can swing across multiple lanes of traffic, leaving other drivers with little time or space to react and increasing the risk of chain-reaction crashes.
- Extreme force and weight: A fully loaded tractor-trailer can weigh up to 80,000 pounds. When that mass folds sideways, the force involved can cause rollovers, cargo spills, or smaller vehicles being crushed beneath the trailer.
- Severe injuries: The impact of a jackknife crash often results in serious harm, including traumatic brain injuries, spinal cord injuries, broken bones, internal organ damage, and, in some cases, fatalities.
- High-speed conditions: Many jackknife accidents occur on highways, interstates, or busy exit ramps, where higher speeds and dense traffic leave little margin for error.
Because of these factors, jackknife accidents frequently lead to widespread damage and life-altering consequences for those involved.
Protecting Your Rights After a Jackknife Accident in San Diego
Jackknife truck accidents in San Diego, California, pose serious risks. When a massive tractor‑trailer folds unpredictably, the results can be catastrophic for individuals, families, and entire communities caught up in the aftermath.
If you or a loved one has been hurt in a jackknife crash, you do not have to face the legal, medical, and financial burden alone. Understanding what happened, who could be responsible, and what kind of help is available gives you a better chance at recovering compensation.
With the right legal guidance, you can pursue justice and regain some control at a time when it otherwise feels like chaos.
For more information, contact an experienced personal injury lawyer at Pines Salomon Personal Injury Lawyers to schedule a free initial consultation today.
We proudly serve San Diego, San Diego County, and its surrounding areas:
Pines Salomon Injury Lawyers – San Diego Office
835 5th Avenue #302, San Diego, CA 92101
(858) 551-2090
Available 24/7
Pines Salomon Injury Lawyers – La Jolla Office
4660 La Jolla Village Dr. San Diego, CA 92122
(858) 585-9031
Available 24/7
