FMCSA and NHTSA Move to Officially Withdraw Speed Limiter Mandate for Heavy Trucks

As announced by Secretary of Transportation Sean Duffy earlier this month, the Federal Motor Carrier Safety Administration (FMCSA) and the National Highway Traffic Safety Administration (NHTSA) have announced the withdrawal of their long-standing proposal to mandate speed limiters on heavy commercial motor vehicles (CMVs). This decision, detailed in Federal Register notice 2025-13928 to be published on July 24, 2025, ends years of debate over requiring electronic speed governors on trucks with a gross vehicle weight rating (GVWR) exceeding 26,000 pounds. Trucking companies, owner-operators, and safety advocates alike have been closely watching this regulatory saga, which aimed to enhance highway safety but faced mounting concerns over costs, data gaps, and potential unintended consequences.

The withdrawal comes amid evolving truck safety technologies and persistent uncertainties in the proposed rule's impacts, marking a win for those opposing mandatory speed restrictions on commercial vehicles. For trucking professionals focused on FMCSA compliance, CMV regulations, and road safety, this move underscores the agencies' emphasis on evidence-based rulemaking while preserving voluntary use of speed limiting devices for those who appreciate their benefits.

Background on the Proposed Speed Limiter Rule for Trucks

The origins of this rulemaking trace back to 2016 when FMCSA and NHTSA jointly issued a Notice of Proposed Rulemaking (NPRM) on September 7, 2016 (81 FR 61942). Responding to petitions from the American Trucking Associations (ATA) and Schneider National, Inc., along with other motor carriers, the agencies proposed requiring heavy-duty trucks equipped with electronic engine control units (ECUs) to limit maximum speeds. The rule would have mandated that these CMVs—typically Class 7 and 8 trucks used in commerce—be capped at speeds between 60 and 68 miles per hour (mph), with carriers required to maintain the settings throughout the vehicle's service life.

The NPRM highlighted potential benefits like reduced crash severity, fuel savings, and emissions reductions. The agencies estimated that a 65 mph limit could save 63 to 214 lives annually, with monetized benefits ranging from $676 million to $2.4 billion, plus $848 million in fuel and emissions savings based on 2013 data. However, the analysis acknowledged limitations, including no estimates for crashes avoided or potentially caused by speed differentials between trucks and passenger vehicles.

In 2022, FMCSA followed up with an Advance Notice of Supplemental Proposed Rulemaking (ANPRM) on May 4, 2022 (87 FR 26317), signaling intent to refine the proposal by focusing on carrier-maintained speed limits for ECUs already in use. This carrier-based approach aimed to address interstate trucking operations more directly, but it reignited familiar debates.

Public comments poured in—over 7,225 for the 2016 NPRM and more than 15,000 for the 2022 ANPRM—from individual drivers, motor carriers, industry groups like the Owner-Operator Independent Drivers Association (OOIDA), safety organizations such as the Insurance Institute for Highway Safety (IIHS), and entities including the National Transportation Safety Board (NTSB).

Supporters of the speed limiter mandate, including groups like Road Safe America, the Truckload Carriers Association (TCA), and the National Safety Council, argued that capping truck speeds would boost overall highway safety, reduce kinetic energy in crashes, and improve fuel efficiency for the environment. Many light-vehicle drivers shared personal anecdotes of dangerous encounters with speeding trucks, urging expansion to all heavy vehicles with existing speed governing equipment. Proponents like Coach USA noted their fleet's successful use of 70 mph limiters for over a decade, emphasizing positive impacts on trucking safety and driver well-being.

Opponents, however, raised alarms about real-world trucking challenges. OOIDA and the American Bus Association highlighted risks from speed differentials, where slower trucks could lead to more passing maneuvers, traffic congestion, and aggressive driving by cars. Commenters worried about increased crash rates on rural interstates, driver fatigue from longer travel times, and economic hits to the industry—such as reduced miles driven affecting pay, higher fuel costs for detours, and supply chain disruptions for time-sensitive loads like agricultural goods. Small owner-operators feared competitive disadvantages, while critics like the Michigan Department of Transportation questioned federal overreach into state speed limit laws.

Few commenters specified preferred speeds, with opinions split evenly among 60, 65, and 68 mph options. International studies were cited but deemed inconclusive for U.S. traffic patterns, where truck sizes, driver behaviors, and road conditions differ.

Reasons Behind the Withdrawal of the Truck Speed Limiter Mandate

FMCSA and NHTSA cited multiple factors for pulling the plug, emphasizing data uncertainties and policy concerns in CMV regulations:

• Data Gaps and Safety Uncertainties: The original analysis lacked reliable estimates for crashes avoided or caused by speed limiters. Emerging technologies like automatic emergency braking (AEB) and forward collision warning (FCW)—mandated in a separate July 6, 2023 NPRM (88 FR 43174)—could mitigate many rear-end crashes involving trucks, overlapping with speed limiter benefits. The agencies noted that voluntary adoption of AEB in heavy vehicles might achieve similar safety goals without mandates.

• Economic and Industry Impacts: Costs ranged widely ($209 million to $1.561 billion annually), but secondary effects like the "rebound effect" on fuel use, driver wages (often mile-based), and delays for other road users were unquantifiable. Small businesses and sectors like agriculture faced disproportionate burdens, potentially exacerbating driver shortages in trucking.

• Federalism and Legal Concerns: The rule could preempt state speed limits, where over half allow trucks above 68 mph on rural interstates. Commenters argued it violated the 1995 National Highway System Designation Act repealing national speed limits (23 U.S.C. 154). Executive Order 13132 on federalism and E.O. 14192 on deregulation further supported withdrawal, viewing the proposal as potentially unlawful or overly burdensome.

• Advancements in Truck Safety Tech: With all modern heavy vehicles already equipped with ECUs, operators can voluntarily set speed limits to capture fuel savings and safety perks. Markets are driving innovations like adaptive cruise control, reducing the need for mandates.

This deregulatory action also aligns with President Trump's E.O. 14192, rescinding significant rules issued before January 20, 2025, based on incomplete statutory grounds.

What This Means for Trucking Companies and CMV Operators

The withdrawal preserves the status quo: no federal mandate for speed limiters on commercial trucks, allowing fleets to implement them voluntarily for safety and efficiency. Trucking compliance experts recommend monitoring state laws, as some may impose local restrictions. Focus shifts to proven technologies like AEB, which FMCSA and NHTSA are advancing to prevent crashes.

For owner-operators and motor carriers, this eases concerns over productivity losses and costs, but highway safety remains paramount. Industry groups like ATA suggest higher voluntary limits (e.g., 70 mph) for AEB-equipped trucks. As trucking evolves with autonomous features and electric vehicles, expect ongoing debates on speed management in CMV safety regulations.

About Trucksafe Consulting, LLC: Trucksafe Consulting is a full-service DOT regulatory compliance consulting and training service. We help carriers develop, implement, and improve their safety programs, through personalized services, industry-leading training, and a library of educational content. Trucksafe also hosts a livestream podcast on its various social media channels called Trucksafe LIVE! to discuss hot-button issues impacting highway transportation. Trucksafe is owned and operated by Brandon Wiseman and Jerad Childress, transportation attorneys who've assisted some of the nation’s leading fleets to develop and maintain cutting-edge safety programs. You can learn more about Trucksafe online at www.trucksafe.com and by following Trucksafe on LinkedIn, Facebook, Twitter, and YouTube. Or subscribe to Trucksafe's newsletter for the latest highway transportation news & analysis. Also, be sure to check out eRegs, the first app-based digital version of the federal safety regulations aimed at helping carriers and drivers better understand and comply with the regulations.