Understanding the FMCSA Speed Limiter Rulemaking
The Federal Motor Carrier Safety Administration (FMCSA) is considering a rule to require speed-limiting devices on heavy trucks. Speed limiters (governors) electronically cap a truck’s maximum speed. Most modern heavy-duty trucks already have electronic engine control units (ECUs) that can enforce speed limits. FMCSA’s interest in a speed-limiter mandate stems from concerns about high-speed crashes: about 20% of fatal crashes in recent years occurred in areas with posted limits of 70–75 mph.
Historically, speed limiter mandates are not new in trucking debates. The National Highway Traffic Safety Administration (NHTSA) studied them as far back as 1991, and the American Trucking Associations petitioned NHTSA for a 68-mph cap in 2006. In 2016, FMCSA and NHTSA jointly proposed speed-limiter rules for trucks, but the proposal was shelved in 2017. The effort revived in 2022 when FMCSA issued an Advance Notice of Proposed Rulemaking (ANPRM) to gather feedback on equipping trucks over 26,000 pounds with speed limiters. This latest NPRM process indicates regulators have again made speed governance a priority for reducing crashes.
Why Speed Limiters Are Being Considered
Safety is the main argument for speed limiters. Data indicate that excessive speed was a factor in nearly one-third of U.S. crash deaths in 2020. For large trucks, speed is even more crucial: due to their mass, trucks have much longer stopping distances and cause more damage in a collision. The Insurance Institute for Highway Safety (IIHS) urged regulators to act quickly to require speed limiters on large and medium-duty trucks, noting that nearly a third of fatal crashes involved speeding and that higher posted limits (some up to 80 mph) only make the problem worse.
Other potential benefits include fuel economy and emissions reductions. The federal analysis for the original NPRM estimated that a 65-mph cap on heavy trucks could save 63 to 214 lives per year and yield up to $848 million in combined fuel and emissions savings. Proponents argued that slower speeds mean less fuel burnt (trucks often see a 5–10% fuel savings for every 5 mph reduction in cruise speed) and lower maintenance costs from reduced wear. Many safety advocates also pointed out that lower speeds reduce kinetic energy in crashes (energy goes up with the square of speed), thereby improving post-crash outcomes.
However, speed limiters are controversial. Opponents (especially owner-operators) warn of unintended consequences. One common concern is that slower trucks create speed differentials: faster cars passing more often could lead to riskier lane changes and congestion. Drivers also worry about longer transit times and reduced earnings (truckers typically earn per mile). Some say that modern safety tech like automatic emergency braking might achieve similar safety goals without mandating a speed cap. Indeed, the FMCSA/NHTSA withdrawal notice in July 2025 mentioned data uncertainties and a focus on technology alternatives. The debate shows a balance between proven safety gains and practical industry impacts.
Current Status and Potential Timeline
As of late 2025, the speed-limiter rule’s future is uncertain. In late 2022, FMCSA signaled it aimed to issue a Supplemental NPRM (SNPRM) by the end of 2023, likely specifying a maximum speed. One report noted that FMCSA had a “target date of Dec. 29 to release an SNPRM” expected to include a top speed. Even if this timeline held, analysts predicted that a final rule would not take effect until well into 2025, given the time needed for public comments and legal review.
However, in mid-2025, political shifts intervened. The Department of Transportation announced that FMCSA (and NHTSA) would withdraw the proposed speed limiter mandate. In a Federal Register notice (July 24, 2025), the agencies officially rescinded the rulemaking. They cited “data uncertainties” in crash statistics and noted that new active safety technologies could address some concerns. For now, the formal rulemaking process is terminated.
Even so, many fleets treat this as “speed limiters on pause.” Safety advocacy and state speed laws remain trends to watch. If a future administration revives the idea or if Congress acts, preparation will pay off. In the meantime, fleets often have internal or state-imposed limits (some states require trucks to go 5–10 mph below the posted speed). Planning as if a federal mandate might return ensures a smooth transition and provides immediate benefits from safer practices.
Key Provisions Under Consideration
Most industry discussions assume a speed-limiter rule would cover vehicles with a gross vehicle weight rating (GVWR) of 26,001 pounds or more in interstate commerce. The likely rule: require that each heavy truck’s ECU be programmed to a top speed (many drafts have considered 65–68 mph). Carriers would be responsible for setting and maintaining that cap. Importantly, FMCSA’s approach emphasizes a carrier-based solution: fleets, not manufacturers, would adjust the limiters on their own trucks.
In practical terms, this means fleets must know how to program limiters on every covered vehicle. Many recent model trucks come with a manufacturer-supported “governor” setting. If mandated, compliance might involve annual calibration checks (similar to how air brakes or speedometers are inspected). Fleets would need to keep records—like calibration certificates or ECM logs—to show inspectors that each truck’s speed limiter is set correctly and hasn’t been tampered with. The FMCSA has indicated that such recordkeeping would parallel existing vehicle inspection requirements.
A federal speed cap would supersede state truck speed laws. Currently, state speed limits for trucks vary (some allow heavy trucks up to 70–75 mph on certain highways, others cap at 65 mph). A single federal limit would standardize trucking speeds nationwide. However, carriers should note that a federal cap would eliminate any higher limits states have; they would have to run trucks at or below the federal maximum even on interstates. Carriers should watch whether Congress tries to block such a rule via rider bills (e.g., the “DRIVE Act”), because ongoing legislative attempts indicate the issue may resurface.
Impact on Fleet Operations
If a speed limiter mandate became reality, fleet operations would need to adapt. Slower top speeds mean longer transit times on long routes. Fleets might have to adjust driver schedules and routes to maintain delivery windows. In a worst-case view, trucks that averaged 70–75 mph overnight might now run 60–65 mph, lengthening trips by perhaps 5–10%. Shippers with just-in-time schedules could request different solutions (like air freight for critical parts). Owner-operators paid by the mile might see a slight income impact if they make fewer miles per day.
On the other hand, many fleets already impose their own speed policies and would see only minor differences. In fact, gradually transitioning to 65–68 mph can reduce fuel consumption. For example, a 5 mph drop in cruise speed often yields a 5–10% fuel economy gain. Given current high diesel prices, that saving can be substantial. Slower speeds also mean engines and tires run cooler, potentially extending maintenance intervals. Some carriers report that by voluntarily capping speeds, they can delay oil changes or reduce brake wear—benefits that help offset any perceived productivity loss.
Safety improvements could also have a financial upside. Lower speeds typically mean fewer severe accidents and lower injury costs. Insurance companies may view a speed-capped fleet as lower risk, possibly translating to lower premiums. Moreover, demonstrating a proactive safety policy can protect a company’s CSA (Compliance, Safety, Accountability) scores. In some business models, safe fleets earn a better reputation with brokers and shippers, which can bring more loads or higher rates. In this sense, a speed limiter is another tool in a comprehensive safety strategy.
Figure: A heavy semi truck traveling at highway speeds. Speed limiters would cap such vehicles to a top speed (commonly proposed around 65–68 mph). In summary, a speed-capped fleet might take slightly longer per trip, but it gains fuel efficiency, lower wear, and enhanced safety. The key is to plan and communicate: coaches or dispatchers can adjust schedules proactively, and safety managers can highlight the improved risk profile.
Steps to Prepare Your Fleet
Fleets do not have to wait for a final rule to start preparing. The following steps can be integrated into regular compliance planning:
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Inventory and Audit Vehicles: List all trucks (and possibly trailers with engine systems) over 26,000 lbs. Note their model years, engine makes, and existing electronic systems. Identify which vehicles have factory-installed speed governors and which might need retrofits or programming tools.
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Consult with OEMs and Service Centers: Reach out to engine and truck manufacturers (e.g., Volvo, Freightliner, Cummins, etc.) to learn how to set or verify the limiter setting. Some OEMs provide software or service bulletins for this task. If you use fleet service providers, inform them of your plan so they can assist with calibration.
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Update Policies and Training: Write a company policy on speed limits. Decide on a target limit (even if voluntary) and document the process for enforcing it. Train drivers that this policy is in effect, emphasizing safety and compliance. Highlight that tampering with any devices (like speed governors or ELDs) is not allowed and will have consequences.
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Use Telematics Data to Plan: Analyze historical GPS/ELD data to see how your fleet is driving now. Identify high-speed routes or drivers who frequently exceed safe speeds. Fleet-Connection advises using telematics to establish baseline speed profiles now. For instance, if most long runs average 68 mph, you know that a 65 mph cap would have minimal schedule impact. On the other hand, if some runs hit 80 mph, those routes will need more adjustment.
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Coordinate with Dispatch and Operations: Dispatchers should be made aware of potential speed limits so they can schedule accordingly. Consider a phased rollout: implement the lower limit on test runs or pilot trucks first, and gather feedback. Update any automated scheduling tools or ETA calculators to factor in the new top speed.
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Prepare Recordkeeping: Add speed limiter actions into your maintenance documentation. When a limiter is set or checked, file a certificate or note in the vehicle’s record (similar to a brake inspection). Keep these records easily accessible so you can prove compliance if asked by auditors later on.
By treating this as part of routine operations rather than an emergency last-minute project, fleets can absorb the change more smoothly. Many of these steps (like audits and driver training) overlap with normal safety management tasks.
Leveraging Telematics for Compliance
Modern telematics systems will be invaluable. These platforms can alert managers in real time if a vehicle nears or exceeds the set cap. For example, you can program an alert if a truck goes above 65 mph for longer than a few seconds. Dispatchers can receive these alerts and coach drivers immediately. This turns enforcement into a proactive process rather than catching speed violations after the fact.
Telematics data can also segment risks. Review speed reports by route and driver. If certain highways or drivers consistently push the limit, they become training targets. Conversely, if a driver runs strictly below the cap on all trips, that data can be used to acknowledge good behavior.
Some systems allow geofenced speed limits. In GPS mapping software, you can define digital zones where different speeds apply (e.g., work zones, school zones, or mountainous areas). Although a federal mandate might enforce one cap nationwide, you can already use this tech to impose even stricter limits in sensitive areas. For instance, if your service area includes a stretch of road with frequent accidents, you could program an even lower speed alert there.
Telematics will also help quantify any effects of speed limiting. You can compare fuel usage, trip times, and driver productivity before and after imposing a limit. These analytics help make the business case internally. For example, if one truck shows 8% fuel savings after the cap, present that to justify the program. Having these facts on hand is especially useful if regulators ask about costs and benefits.
Finally, integrate telematics with compliance records. Many fleets now automate report generation. You could schedule a monthly report of “speed alert events” to be emailed to management. This ensures that documentation of your speed policy (and its enforcement) is woven into your normal audit trail. When regulators arrive, you’ll have a clear timeline showing how the policy was applied.
Figure: Telematics data and speed governors ensure trucks don’t exceed safe speeds. Advanced fleet platforms can alert dispatchers when a vehicle approaches the speed cap. These monitoring tools turn a potential rule (speed limiting) into actionable safety operations today.
Driver Training and Policy Updates
Technical changes alone are not enough—people and processes must adapt. Begin by educating drivers about the new speed policy. Explain the rationale clearly: safety first, plus efficiency gains. Let them ask questions about how this affects their routes and pay. Emphasize that the speed cap is a company policy aligned with potential future law, and stress the importance of compliance.
Key points for drivers:
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Keep to the set maximum speed (e.g., 65 or 68 mph). Explain how this fits with hours-of-service calculations and break schedules.
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Plan routes and breaks, knowing that travel will be slightly longer. If needed, adjust pick-up and delivery times.
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Never attempt to override or tamper with the limiter device. Remind them that, as with tampering with ELDs, this would violate company policy and FMCSA rules.
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Share fuel-saving tips at lower speeds (such as gentle acceleration and anticipating traffic). Drivers often appreciate learning to save fuel, since it can justify the slower speed.
Dispatchers and operations staff also require training. They should learn how to read speed reports and alerts from the telematics system. They will need to recalculate estimated times of arrival under the new cap and communicate any schedule changes to customers. Encourage them to use route planning tools that factor in reduced speeds. For example, using a mapping service with updated truck speed preferences helps ensure ETAs remain accurate.
Consider running practical exercises. Have a few trucks run with a cap and analyze the differences. If possible, schedule a mock trip at 65 mph so dispatch can see the impact on timing. Use successful experiences from veteran drivers: if some drivers adapt well, highlight their approach. Positive reinforcement helps build acceptance.
Drivers may worry about pay. If your company pays by mile, explain how the speed cap is factored into rates or bonuses. Some carriers create incentives tied to compliance (for example, a fuel economy bonus or a safety score recognition). Aligning rewards with safe driving makes the policy more palatable.
Voluntary Adoption and Benefits
Fleets that adopt speed limiting voluntarily often see benefits before any rule is forced. For instance, fuel savings can translate into extra earnings for drivers or margin for the company, even with a slightly slower pace. Lower speed also typically means fewer accidents; even a small reduction in crash frequency saves costs and downtime.
If your company hasn’t tried this before, start small. Have a handful of drivers try limiting at 65 mph and track their fuel economy. Chances are you’ll see immediate drops in fuel use and smoother driving habits. Share these wins company-wide. Over time, these small improvements compound: less fuel, less wear and tear, fewer fines.
Emphasize to drivers that this is not a loss of autonomy, but an investment in their safety and income. Many professional drivers already prefer a steady 65 mph cruise because it’s easier on the body during long shifts. Promote that narrative. In the long run, operating at a more conservative speed tends to attract quality drivers who value safety.
Environmental benefits should not be overlooked. Lower speeds reduce CO2 output, which fits many companies’ ESG goals. In the age of sustainability reporting, being a fleet that already runs cleaner can be a marketing advantage.
In all, treating a speed limiter policy as a value-add rather than a burden changes the internal conversation. With the right approach, fleets can come out ahead whether or not the federal rule ever returns.
Industry Resources and Training
Support is available from industry experts. For compliance and operations guidance, consider firms like Trucking42. Trucking42 provides a suite of services—dispatching, safety audits, regulatory compliance and more—that can help integrate a speed-limiting policy. In particular, their dedicated Dispatch Services team can optimize loads and routes while accounting for speed caps. Outsourcing some of the logistics planning to experienced professionals can relieve the burden on your internal staff during this transition.
Training programs are also beneficial. For example, the Dispatch 42 School truck dispatcher course teaches dispatchers how to efficiently plan freight runs in compliance with safety and regulatory requirements. Enrolling your logistics team in such a course can sharpen their skills in routing, load balancing, and compliance. A well-trained dispatcher will be better equipped to manage driver schedules under the new speed constraints.
Stay informed via official and trade sources. FMCSA’s website has a Speed Limiters Notice of Intent FAQ page with background on the rulemaking at fmcsa.dot.gov. Industry publications like Land Line and FleetOwner regularly report on developments landline media. Subscribing to newsletters or bulletins from trucking associations (such as ATA or TCA) ensures you won’t miss any policy updates. Peers and mentor networks (like Truckload Carriers Association forums) are also useful for best-practice sharing.
Figure: Proactively setting trucks to a speed cap (e.g., 65 mph) using ECU programming. With most modern trucks already equipped with electronic control modules, a mandated limiter is technically feasible. Expert resources emphasize that since post-2010 trucks already have ECUs, programming a limit is straightforward. By leveraging these industry supports, fleets can accelerate their readiness for any future rule.
Expert Perspective and Best Practices
Experts advise treating speed limiting as an extension of your existing safety management system. Form a cross-functional team—maintenance, safety, operations, and IT—to handle this initiative. For instance, your maintenance crew can ensure limiters are properly calibrated, while safety staff track crash and compliance data. Hold regular review meetings to update leadership on progress and metrics (speed alerts, fuel use, compliance status). This keeps the issue on the radar and ensures accountability.
Documentation is critical. Record every action related to speed limiters: policies, driver acknowledgments, maintenance checks, and training sessions. Store these in your safety management system so that any regulator or auditor can see a clear timeline of how the policy was implemented. This mirrors how fleets track other changes (such as ELD adoption or drug-testing programs).
Pilot programs are recommended. Start with a few trucks on simple routes and fine-tune your processes. This phased approach, suggested by fleet consultants, lets you learn before a full rollout. Gather driver feedback from the pilot; their real-world insights help avoid bigger issues later. Once confidence is built, expand to more trucks.
Finally, communicate wins. If crash rates drop or fuel consumption improves after implementation, share those results internally. This builds support for the program. If regulators ask whether a speed policy works, you’ll have data to show it does. Staying proactive—even in a period when the mandate is withdrawn—positions your fleet as a safety leader and minimizes future disruptions.
Conclusion
The FMCSA speed limiter rulemaking highlights an ongoing emphasis on roadway safety. Fleet managers and telematics providers can turn this potential regulation into an opportunity. By auditing trucks, leveraging technology, training teams, and documenting every step, you lay the groundwork for smooth compliance. Doing so not only prepares you for a possible mandate but also delivers immediate benefits: fewer accidents, lower fuel costs, and stronger regulatory performance.
Stay engaged with FMCSA guidance and industry news. Use resources like Trucking42’s services and the Dispatch42 School to build in-house expertise. The bottom line: treating speed management as a core part of your safety culture will keep your fleet safe, efficient, and ready for whatever regulations lie ahead.
