A routine highway drive can turn catastrophic in seconds when a car slides beneath the rear of a semi-truck, often triggered by sudden stops, low visibility, or poor maintenance of underride guards. The force of impact can shear off the top of the vehicle, leaving victims disoriented, critically injured, or worse.
Several factors make underride crashes especially severe: the design of semi-trucks, height mismatches with passenger vehicles, and missing or poorly maintained underride guards. At highway speeds, even a single failure can lead to devastating consequences.
For more than 40 years, Buchanan, Williams & O’Brien has earned the trust of clients across Missouri, bringing local insight, proven results, and the integrity our clients have trusted for decades. In an underride accident, we gather evidence, navigate claims, and pursue the compensation and accountability you need under Missouri law. Schedule a free consultation today..
What Is an Underride Crash?
An underride crash occurs when a smaller vehicle slides beneath the rear or side of a commercial truck. In such collisions, the car’s roof and structural supports are often crushed, the windshield shatters, and the upper frame collapses, severely compromising the passenger compartment and offering little protection for those inside.
Common Causes of Truck Underride Accidents
There is rarely a single cause behind an underride crash. Instead, these accidents usually involve a combination of roadway conditions, driver behavior, and maintenance issues.
Some of the most common factors include:
- Sudden stops or slow-moving trucks, especially at night or in poor visibility
- Missing or damaged underride guards that fail to prevent a vehicle from sliding underneath the trailer
- Poor lighting or reflective markings making it difficult for approaching drivers to judge distance
- High rates of speed, which reduce reaction time and increase impact force
- Unsafe turns or lane positioning, particularly during wide right turns
When underride crashes occur, investigators often examine whether the truck was properly equipped with underride guards, whether appropriate warning signals were used, and the trucking company’s safety and maintenance history. They may also review eyewitness statements, dashcam or surveillance footage, telematics data, and event data recorders to reconstruct the crash.
The Role of the Underride Guard
Underride crashes are often preventable, and one of the most important safety features is the underride guard. It is a metal bar or framework mounted on the rear or side of a truck trailer. Its purpose is simple: to stop a passenger vehicle from sliding underneath during a collision. When properly designed and maintained, it can dramatically reduce the severity of injuries.
Unfortunately, underride guards don’t always perform as intended. Some underride guards are too weak to withstand high-speed impacts due to material limitations, design flaws, manufacturing defects, or improper installation. Even guards that meet basic standards may fail if they’re worn, damaged, or mounted too high, leaving a dangerous gap that allows smaller vehicles to underride the trailer.
Because underride guards play such a critical role in preventing catastrophic injuries, federal regulations govern their design, placement, and maintenance, but gaps remain.
FMCSA Underride Guard Regulations and Safety Gaps
Under federal law, commercial trailers with a gross vehicle weight rating of more than 10,000 pounds are required to have rear underride guards to protect smaller vehicles in a crash.
However, compliance with federal trucking safety regulations does not always mean a truck is truly safe. Here’s why:
- Current FMCSA regulations only require rear underride guards, leaving side underride accident risks unaddressed.
- The regulations were developed decades ago and tested at lower speeds, not accounting for modern passenger vehicles, SUVs, or high-speed highway crashes.
- Even “compliant” guards may fail if poorly maintained, damaged, or improperly mounted.
When an underride guard fails during a crash, investigators may examine whether the guard met minimum standards, whether it was properly maintained, and whether stronger or safer designs were available. These questions can open the door to liability beyond the truck driver to other parties.
Liability in a Truck Underride Accident
Determining fault after an underride crash can be complex and may involve:
- The trucking company for failing to properly install, maintain, or inspect underride guards.
- The truck driver, if negligence contributed to the crash, for example, unsafe lane changes, speeding, or failing to monitor blind spots.
- The trailer manufacturer for defective underride guard design or manufacturing.
- A maintenance provider if inspections or repairs were inadequate.
- Other motorists, if another vehicle’s reckless actions triggered a chain reaction that led to the crash
How Modified Comparative Negligence May Affect Your Claim
Missouri follows a modified comparative fault system, meaning that a crash victim can still pursue a claim even if they are partially at fault. Since your award could be reduced based on your percentage of fault, you’ll want to work with a skilled truck accident lawyer to ensure your claim accounts for all liable parties, protects your rights, and maximizes the compensation you deserve.
Why Underride Crashes Are So Dangerous
A passenger vehicle’s crumple zones offer little protection because the car slides under the truck trailer. The point of impact is often at head and chest level, where airbags and seatbelts provide limited defense.
As a result, the most common injuries include:
- Head and brain trauma: The windshield or roof may strike the occupant’s head directly, causing concussions, skull fractures, or traumatic brain injuries.
- Neck and spinal injuries: The upper body can be compressed, leading to broken vertebrae, spinal cord damage, or paralysis.
- Chest and internal injuries: Rib fractures, collapsed lungs, and damage to internal organs occur when the chest is crushed between the roof and steering wheel or dashboard.
- Severe lacerations and broken bones: Shattered glass, collapsing A-pillars, and deformed metal can cause deep lacerations and multiple fractures.
Survivors often face lifelong medical care, permanent disabilities, and lost earning capacity. Slight differences in guard design, trailer height, or speed can mean the difference between life and death.
Schedule a Free Consultation
If you or a loved one has been injured in a truck accident in Missouri, early investigation is critical. Evidence involving underride guards, vehicle damage, and federal compliance can disappear quickly, and gathering it promptly can make a real difference in your claim.
Buchanan, Williams & O’Brien, P.C. helps accident victims and their families navigate the complex process of pursuing a truck accident claim in Joplin, Springfield, St. Louis, and across Missouri. From collecting evidence and reviewing safety compliance to negotiating with insurers, our team works tirelessly to help clients pursue the full compensation and accountability they need for their losses.
Schedule a free, no-obligation consultation today.