Semi-Truck Accident Lawyer in Castle Rock
A fully loaded semi can weigh close to 80,000 pounds. Your car probably weighs about 3,200 (depending on the size, make and model). That is a 25-to-1 weight ratio, and when those two vehicles collide at highway speed, physics does not compromise. In 2023, 5,472 people were killed in large truck crashes across the United States, and 82% of them were not in the truck. (NHTSA Large Trucks: 2023 Data). If a semi-truck crash in Colorado changed your life, Rampart Injury Lawyers fights for people like you across the I-25 corridor. Call (303) 766-8766.
The Physics of a Semi-Truck Collision
You do not need an engineering degree to understand why semi-truck crashes are so much worse than car crashes. You just need two numbers.
A typical sedan weighs between 3,000 and 4,000 pounds. A fully loaded semi-truck and trailer combination can legally weigh up to 80,000 pounds on federal highways. Some configurations with special permits exceed even that. The weight ratio is 20-to-1 at minimum. In most crashes, it is closer to 25-to-1.
The semi-truck’s mass is what causes its increased kinetic energy. If the semi (loaded) is moving at 65 miles per hour it will have approximately twenty-five (25) times as much kinetic energy as a loaded sedan moving at the same rate. When a semi-truck collides with a sedan, the sedan takes almost the entire force of the collision. Thus, when a semi-truck crashes into an automobile, the truck doesn’t slow down that much, but the automobile crushes; and the individuals in the automobile are the ones to absorb the brunt of the force from the crash.
Stopping Distance: The 225-Foot Gap
At 65 mph, a passenger car needs roughly 300 feet to come to a full stop. A loaded semi-truck needs approximately 525 feet. That is nearly two football fields. The difference between those two numbers, 225 feet, is where rear-end semi-truck crashes can happen. So when traffic ahead slows suddenly on I-25, the car behind you might be able to stop, but a semi truck might not if it is following too closely.
This is even worse when the roads are wet or the brakes are worn in. A downhill grade such as the one on Monument Hill makes it worse. And a driver who was awake for 14 hours and fighting to keep their eyes open makes it catastrophically worse.
The Height Problem: Underride Crashes
A semi-trailer rides at a height that lines up almost exactly with the windshield and passenger compartment of a sedan or SUV. When a car slides beneath the trailer in a rear-end or side-impact collision, the trailer shears the roof off the passenger compartment. The occupants have no crumple zone, no airbag deployment, no protection. Their vehicle’s safety systems were designed for frontal and lateral impacts.
Federal law has required rear underride guards on semi-trailers since 1998 under FMVSS Nos. 223 and 224, originally issued in 1996. NHTSA updated the strength standard in 2022 to require guards to withstand a 35 mph impact (up from 30 mph), but critics including former NHTSA Administrator Joan Claybrook called the update inadequate. Side underride guards are not federally required, though the Bipartisan Infrastructure Law directed NHTSA to study and consider rulemaking on side guard requirements. When a guard fails or a side underride occurs, liability could extend to the trailer manufacturer, the fleet owner, and the entity responsible for maintenance. For more on this crash type, see our underride truck accident page.
The Cargo Factor
A semi-truck’s cargo changes everything about how it handles. A tanker carrying liquid will have its weight shift through every curve and bump on the road. A flatbed with improperly secured steel becomes a projectile launcher in a collision. A refrigerated trailer with an unbalanced load rolls over on a curve that a properly loaded truck would survive.
Federal cargo securement standards under 49 CFR Part 393, Subpart I specify tie-down requirements for every type of cargo. When the shipper or loader violates those standards and the cargo contributes to a crash, the loading party shares liability. Your lawyer needs to identify who loaded the trailer and whether they followed the rules.
Why Semi-Truck Accidents Cause Catastrophic Injuries
The math tells us why these accidents are so tragic and often catastrophic. When a semi truck can weigh close to 80,000 pounds and hits a 3,200 pound car, the smaller vehicle does not stand a chance. The injuries that come out of semi-truck collisions are not fender-bender stuff. They can be life-changing.
Traumatic brain injuries happen when the occupant’s head strikes the interior of the vehicle, when the vehicle structure intrudes into the passenger compartment, or when the sudden deceleration causes the brain to impact the inside of the skull. The force involved in a semi-truck collision multiplies all of these mechanisms. Many TBI victims do not know they have a brain injury until weeks later, when the headaches do not stop and the words do not come. Our Colorado brain injury lawyers page explains what to watch for.
Spinal cord injuries from semi-truck crashes can produce paraplegia or quadriplegia. The forces involved in these collisions compress, fracture, or sever the vertebrae and the spinal cord they protect. These are lifetime injuries. The medical costs alone can exceed $5 million over a lifetime, depending on the level of the injury. See our Colorado spinal cord injury lawyers page for more.
Internal organ damage, crush injuries, severe burns, and amputation are all disproportionately common in semi-truck collisions. When fuel tanks rupture, fires follow. When the cab collapses around the occupant, extrication takes hours. When a limb is pinned between vehicles, the trauma surgeons face decisions no one should have to make.
And then there is death. In 2023, 82% of the people killed in large truck crashes were occupants of the other vehicle, pedestrians, or cyclists. Not the truck driver. (NHTSA 2023). If a semi-truck crash killed someone you love, our Colorado wrongful death lawyers can help your family.
Who Is Liable When a Semi Hits Your Car?
In a regular car accident, it is usually one driver’s insurance company that you can hold responsible. In a semi-truck case, the answer is often four or five separate parties, each with their own insurance, each potentially on the hook for your damages.
The Driver
The truck driver may be liable for speeding, distracted driving, fatigued driving, impaired driving, or failure to perform a pre-trip inspection. In 2022, at least one driver-related factor was recorded for 33% of large truck drivers involved in fatal crashes. (FMCSA Large Truck and Bus Crash Facts 2022).
The Motor Carrier
The trucking company that employs or contracts the driver is liable under the doctrine of respondeat superior for negligent acts committed within the scope of employment. The carrier can also face direct liability for negligent hiring (did they check the driver’s record?), negligent supervision (did they monitor HOS compliance?), negligent maintenance (did they keep the brakes and other safety equipment in working condition?), and negligent entrustment (did they give this truck to a driver they knew was unfit?).
The Freight Broker
Freight brokers arrange loads between shippers and carriers. When a broker selects a carrier with a poor safety record, or pressures a carrier to meet an unrealistic delivery timeline, the broker may share liability for a resulting crash. Broker liability is an evolving area of law. Your lawyer should analyze the broker’s role in every semi-truck case.
The Shipper or Loader
If the cargo was loaded improperly, overweight, or not secured according to federal standards, the party who loaded the trailer can be liable. Shifted cargo changes a truck’s center of gravity and handling characteristics. On a curve, that shift can cause a rollover. See our truck rollover page.
The Maintenance Provider and Parts Manufacturer
If a brake system failed because the maintenance company cut corners, or a tire blew out because of a manufacturing defect, those parties are liable too. FMCSA vehicle maintenance standards (49 CFR Part 396) require systematic inspection of every commercial vehicle. When a component fails because someone did not follow those standards, the paper trail leads back to whoever signed off on the last inspection.
Federal Regulations That Apply to Semi-Trucks
Every semi-truck on Colorado’s highways operates under federal regulations enforced by the FMCSA. These rules exist because the consequences of a semi-truck crash are catastrophic, and the most common causes, fatigue, impaired driving, and poor maintenance, are preventable through regulatory compliance.
Hours of Service (49 CFR Part 395): Property-carrying drivers are limited to 11 hours of driving within a 14-hour window after 10 consecutive hours off duty. Weekly limits cap driving at 60 hours in 7 days or 70 hours in 8 days. A mandatory 30-minute break is required after 8 cumulative hours.
Electronic Logging Devices: Since December 2017, most commercial drivers must track driving time using ELDs that connect to the truck’s engine. The device records when the engine runs, when the vehicle moves, and how many miles it covers. It switches to driving mode automatically above 5 mph. The data creates a timeline of the driver’s movements before any crash. But motor carriers only have to retain ELD data for six months. (FMCSA ELD Rule).
Drug and Alcohol Testing: Commercial drivers face mandatory testing before employment, randomly, after qualifying accidents, and on reasonable suspicion. As of mid-2025, more than 190,000 CDL drivers were in prohibited status in the FMCSA’s Drug and Alcohol Clearinghouse, roughly 1 in 30 CDL holders nationwide. (US Compliance Services, 2025).
Vehicle Maintenance (49 CFR Part 396): Prior to departure and upon completion of a trip, the inspection of a truck is required. The inspection should include brake systems; tire condition; steering system operation; headlight, taillight and other necessary light source operation; and coupling device functionality, all of which should be within specified requirements. When an operator does not inspect as they should, or when an operator delays repair of a vehicle for cost reasons, and a component fails, then those records will serve as proof of the operator’s failure to properly maintain the vehicle.
For a complete plain-language breakdown of every regulation that matters in a Colorado truck accident case, read our FMCSA Trucking Regulations Guide.
What Rampart Does Differently in Semi-Truck Cases
Most personal injury firms treat a semi-truck accident like a bigger car accident. They request the police report, collect medical records, and send a demand letter. That is not how we work.
Every semi-truck case is prepared as if it will go to trial. The preparation of your case is what drives the value for either settlement or a jury verdict. The trucking company’s defense team can tell the difference between a lawyer who has only sent a demand letter and a lawyer who has already retained an accident reconstruction engineer, subpoenaed the ELD data, pulled the carrier’s FMCSA safety profile, scheduled the driver’s deposition, etc.
Preservation demand as soon as possible. We usually send written demands to the carrier, their insurer and registered agent for immediate preservation of evidence such as ELD records, dash cam footage, in-cab camera video, driver qualification files, dispatch communications, maintenance records, and the vehicle itself. If the carrier destroys evidence after receiving our letter, we can pursue later sanctions.
Independent accident reconstruction. Our engineers will often analyze such things as vehicle speed; how far it was to stop (braking distance); where the vehicle struck (point of impact), and what the vehicle was doing (vehicle dynamics) based upon the physical evidence left at the scene; the EDR (event data recorder) data from the vehicles involved in the collision; and all photographs taken of the scene and vehicles.
FMCSA safety profile review. We pull the carrier’s complete record from the SAFER system as soon as possible which includes: CSA scores, inspection violation rates, out-of-service percentages, crash history, and any compliance reviews or enforcement action against the carrier. A carrier with a documented pattern of safety violations is a carrier that had notice and did nothing.
Trial preparation from day one. Insurance companies calculate the value of your case based on what they think will happen at trial. When they see a lawyer who has done the work, who has the evidence, and who will put it in front of a jury, the settlement number moves. We have recovered millions for Colorado families by doing exactly this. That is the difference between speed and value.
Frequently Asked Questions: Semi-Truck Accidents in Colorado
What is the difference between a semi-truck and other large trucks?
A semi-truck, also called a tractor-trailer, 18-wheeler, or big rig, is a combination vehicle with a tractor unit pulling one or more trailers. When fully loaded, the combination can legally weigh up to 80,000 pounds. Other large trucks include single-unit vehicles like box trucks and dump trucks that carry cargo on the same frame as the engine. In 2022, tractor-trailers accounted for 59% of all large trucks involved in fatal crashes, making them the deadliest category by a wide margin. (NHTSA FARS 2022 Data).
How much does a semi-truck weigh compared to a car?
Fully loaded, a semi-truck can be as heavy as 80,000 pounds. Most automobiles (passenger cars) will weigh from about 3,000 to 4,000 pounds. The ratio of weight for a semi and a car is therefore approximately 20:1 to 25:1. Due to the fact that kinetic energy increases with the mass of an object, a semi traveling down the highway at a moderate rate has roughly twenty-five times the destructive energy of a car going at the same rate. Therefore, it is not surprising that 82% of those who lose their life in a collision involving a large truck are occupants of the vehicle involved in the collision that was less massive.
What is the stopping distance of a semi-truck?
A fully loaded semi traveling at 65 mph needs approximately 525 feet to stop. A passenger car at the same speed needs about 300 feet. The 225-foot gap is where most rear-end semi-truck crashes happen. Wet roads, worn brakes, or a downhill grade increase that distance even further.
What should I do after a semi-truck accident in Colorado?
The first thing to do is get to safety and call 911. Then you can start to gather evidence if you feel okay enough to do so, which can include: photographing the truck, its license plate, the USDOT number on the cab door, all visible damage, and the road conditions. Do not give a recorded statement to the trucking company’s insurance adjuster. Seek medical attention if you have any indication at all that you may have sustained injuries, because adrenaline can mask pain and not all injuries are readily apparent. Then, contact a semi-truck accident lawyer as soon as possible because evidence in these cases begins disappearing within hours. Read our full guide: What to Do After a Truck Accident.
How long do I have to file a semi-truck accident lawsuit in Colorado?
Colorado’s statute of limitations for personal injury is three years from the date of the accident under C.R.S. 13-80-101. For wrongful death, it is two years. But the legal deadline is not the practical deadline. ELD data can be overwritten quickly and dashcam footage disappears. The fact of the matter is the sooner your lawyer begins the investigation, the stronger your case.
What is the minimum insurance a trucking company must carry?
The federal government requires that all common carrier’s liability insurance be a minimum of $750,000 for liability coverage and as much as $5,000,000 when they are carrying hazardous materials. (49 CFR Part 387). Since 1980, these minimums have never changed. Often times the actual damage from a catastrophic wreck can exceed the liability limits by many times over. Therefore it is necessary to identify and verify the liability limits on each party involved in an accident so that you can determine which policy will apply.
Can I sue the trucking company, or only the driver?
The short answer is you can probably sue both. Under the doctrine of respondeat superior, a trucking company is liable for the negligent acts of its employees. The company can also face direct claims for negligent hiring, negligent supervision, negligent maintenance, and negligent entrustment. We identify every liable party and every insurance policy in every case.
What if the semi-truck driver was on drugs?
The Federal Motor Carrier Safety Administration (FMCSA) requires carriers to have a post-accident drug test for drivers within 32 hours of an accident. The FMCSA’s Drug and Alcohol Clearinghouse keeps records of all violations. By 2025, approximately 1 in 30 CDL holders nationwide will be in prohibited status. Therefore if a carrier places a prohibited driver behind the wheel of a CMV, the carrier has increased its liability risk significantly. It is best to obtain data from the Clearinghouse at the beginning of each case because you never know if they were doing the right thing or not until you check.
A Semi Changed Your Life. We Can Help You Fight Back.
We have helped folks along the I-25 corridor and across Colorado who were hit by semis, rear-ended at stoplights, crushed in construction zones, and T-boned at intersections by drivers who should never have been behind the wheel.
Call (303) 766-8766
or fill out the form below.
The consultation is free. If we take your case, you pay nothing unless we win.
No fee unless we recover compensation for you. Clients may be responsible for costs and expenses regardless of outcome.
Related Resources
- Colorado Truck Accident Lawyers (Pillar Page)
- 18-Wheeler Accident Lawyer Colorado
- Jackknife Truck Accident Lawyer
- Truck Rollover Accident Lawyer Colorado
- Truck Driver Fatigue Accident Lawyer
- Truck Tire Blowout Accident Lawyer
- Truck Accident Settlement Colorado
- Underride Truck Accident Lawyer Colorado
- FMCSA Trucking Regulations Guide
- What to Do After a Truck Accident
- I-25 Truck Accident Lawyer Colorado
- Colorado Brain Injury Lawyers
- Colorado Spinal Cord Injury Lawyers
- Colorado Wrongful Death Lawyers
Sources
- NHTSA, Large Trucks: 2023 Data
- NHTSA, Overview of Motor Vehicle Traffic Crashes in 2023
- FMCSA, Large Truck and Bus Crash Facts 2022
- NHTSA FARS 2022 Data (body type classification)
- 49 CFR Part 395, Hours of Service (eCFR)
- FMCSA, Electronic Logging Devices (ELD) Rule
- FMCSA Drug and Alcohol Clearinghouse
- US Compliance Services, FMCSA Clearinghouse Update (2025)
- 49 CFR Part 396, Inspection, Repair, and Maintenance (eCFR)
- 49 CFR Part 393, Subpart I, Cargo Securement (eCFR)
- 49 CFR Part 387, Financial Responsibility (eCFR)
- FMCSA SAFER System
- FMCSA Homepage
- C.R.S. 13-80-101, Statute of Limitations
- C.R.S. 13-21-111, Comparative Negligence
