Setting The Record Straight On Twin 33 Trailers

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Earlier this week, during the Senate Commerce Subcommittee on Surface Transportation and Merchant Marine Infrastructure, Safety, and Security hearing on truck safety, testimony incorrectly represented the potential safety and operational impacts of the widespread use of Twin 33 trailers, which are already allowed on portions of highways in 20 states nationwide.

Outlandish claims about the safety of this configuration undermine the abilities of this advanced equipment to help shippers meet the demands of the modern consumer.

Please see below for more information on the real benefits of Twin 33 trailers.


Myth: Larger trucks, like Twin 33s, are more likely to be in accidents, threatening the safety of our roads.

Fact: Nationally, twin-trailer trucks have crash rates that are among the lowest in trucking, and among all types of motor vehicles. In 2014, large trucks traveled 9.2 percent of all U.S. vehicle miles, while only accounting for 2.9 percent of accidents involving injury and 4.5 percent involving property damage. For fatal crashes, larger trucks account for 8.3 percent, once again below the percent miles driven by large trucks. (Source)

For Twin 33s specifically, FedEx and UPS have had zero accidents in their pilot programs in Florida.

Myth: Increasing the length of truck trailers also increases the likelihood of truck accidents.

Fact: Research has shown that truck length and crash rate actually have an inverse relationship. In a university analysis in Sweden, long units (double or triple trailers) had the lowest crash rates among all those examined, followed by medium, and then short-length trucks. Thus, rather than vehicle size, the findings point to driver performance, vehicle condition and equipment, and traffic conditions as the true factors contributing to truck crash rate. (Source)

Myth: Twin 33s would increase the size of trucks driving down Main St. in local communities.

Fact: Twin 33s will only ever travel on national highways, where Twin 28s currently operate.   Proposals before the Senate, passed with bipartisan support in the House, would not create changes to where twin trailers operate on the national road network.

Myth: The Twin 33 proposal would “override the laws of many states.”

Fact: Current federal law requiring states to allow the operation of Twin 28′ trailers gives them wide discretion to determine the appropriate routes on which these trucks can operate, and states may prohibit them from using a route that they determine is unsafe. This would not change under any proposed legislation supported by the Americans for Modern Transportation coalition.

Myth: Carriers will be forced to replace existing trailers with Twin 33s.

Fact: Carriers will neither be required nor forced to replace existing fleets with Twin 33 trailers. The decision to invest in Twin 33s will be reserved for individual carriers. Many carriers will be encouraged to invest based on 2014 data: Twin 33s can save $2.6 billion annually due to productivity gains over current Twin 28 trailers. (Source)

Myth: Twin 33 trailers give truckload operator’s competitors an unfair advantage in the shipping industry.

Fact: Twin 33s will mainly be used in the less-than-truckload industry’s hub and spoke operations that mainly serve retail businesses transporting manufactured goods. If Twin 33s were to be federally authorized, single 53′ trailers would “continue as the workhorse for truckload operations carrying more than 97 percent of highway freight by weight.” (Source)