What Are Speed Limiters – and Why Don’t Trucking Companies Use Them?

The Federal Motor Carrier Safety Administration (FMCSA) plans to unveil its final proposal on speed limiters and commercial trucks sometime later this year. Currently, speed limiters (which work like they sound – they restrict a vehicle from going above a certain speed) are not required in the United States. However, the FMCSA plans to make this technology mandatory over the next few years in commercial vehicles.

Back in April 2022, the organization put out a Notice of Intent to publicize their plan to make speed limiters mandatory in CMVs:

FMCSA is moving forward with this rulemaking because of concerns about the number of CMV crashes and fatalities traveling at high speeds. In 2019, there were 860 fatal crashes in areas with posted speed limits of 70 to 75 miles per hour. Twenty-four fatal crashes in areas with posted speed limits between 80 to 85 miles per hour. Approximately 20 percent of fatal crashes occur in areas with posted speed limits in these ranges. The rule will help reduce crashes and save lives on our nation’s roadways.

Both trucking companies and safety advocates offered their input on this announcement, with their reactions mixed.

For example, critics of the program believe speed limiters could cause more truck accidents. Their argument is that if commercial trucks are unable to travel at the same rate of speed as traffic, the differential could be dangerous. They also say speed limiters could cause “rolling roadblocks” if trucks are in both lanes. Or, passenger car drivers could get frustrated with “slow” trucks and cause accidents trying to pass them.

Safety advocates, however, report that the use of speed limiters offers fuel savings and safety benefits.

The Truck Safety Coalition in particular notes that speed is a “significant factor in fatal crashes and speed management [is] a primary tool to reduce serious injuries and fatalities.” They also point out that over 1,000 Americans are killed every year because of speeding trucks, and that the United States is the only leading country without standard commercial vehicle speed limiters:

An Ontario Ministry of Transportation study found that speed-related, at-fault collisions involving large commercial vehicles fell by 73% after the speed limiter requirement went into effect.

The same study ALSO found there is “absolutely no evidence” speed limiters contributed to an increase to inadvertent crashes w/passenger vehicles due to differences in speed.

And, did you know that rulemaking requiring the use of speed limiters in CMVs has been delayed over 20 times in the past 10 years? Per the Truck Safety Coalition, the “FMCSA must expeditiously complete rulemaking to require compel the use of speed limiters installed on Commercial Motor Vehicles.”

Read more about the FMCSA’s Notice of Intent here.

How do speed limiters work?

Speed limiters for commercial trucks are electronic devices that restrict the maximum speed at which the vehicle can travel. These devices are typically installed in the engine control module and limit the truck’s speed to a predetermined maximum, which is usually set by the manufacturer, federal regulations, or company policies. The use of speed limiters is intended to improve safety by reducing the risk of accidents caused by excessive speed, as well as improve fuel efficiency and reduce wear and tear on the vehicle.

Speed limiters generally work by electronically controlling the maximum speed at which the vehicle’s engine can operate. The device is connected to the truck’s engine control module, which is responsible for regulating fuel and air supply to the engine. When the speed limiter is activated, it sends a signal to the engine control module, which restricts the amount of fuel and air that can be supplied to the engine. This, in turn, limits the engine’s power output, which limits the maximum speed at which the truck can travel. The specific way that a speed limiter works can vary depending on the manufacturer and the model of the device, but the basic principle is to limit the engine’s power output and thus the vehicle’s speed.

Can speed limiters help reduce truck accidents?

It’s likely they can and will:

• By restricting the speed of commercial trucks, speed limiters can reduce the risk of accidents caused by excessive speed. Speeding is a major contributor to crashes involving tractor-trailers and commercial vehicles, and limiting their speed can help mitigate this risk.
• Speed limiters can help to reduce the severity of accidents if they do occur. When a truck is traveling at a high speed, the force of impact in a crash can be much greater than at a lower speed. Limiting a commercial truck’s speed can help reduce the force of impact and the severity of injuries in the event of a crash.
• Speed limiters can also help promote safer driving practices among commercial truck drivers. When drivers know that their vehicles are equipped with speed limiters, they are more likely to drive at a safer and more appropriate speed, which helps reduce the risk of accidents.

Overall, speed limiters can be an effective tool for reducing the risk and severity of accidents involving commercial trucks, making the roads safer for all users.

Our attorneys are keeping an eye on this issue and will update you when the FMSCA unveils their final proposal.

In the meantime, if you or someone you love are injured in a truck accident, we want to help. The lawyers at Phelan Petty have been helping people involved in commercial truck crashes for decades, and we can help you too. We will walk you through the legal process, negotiate with insurance companies on your behalf, and see your case through to a successful outcome. You deserve financial compensation when you’re injured in an accident that wasn’t your fault.

To set up a free initial consultation, call our Richmond office today or fill out our contact form to talk about your case with a skilled attorney. Serving all of Virginia.

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