Title 49 › Subtitle SUBTITLE VI— - MOTOR VEHICLE AND DRIVER PROGRAMS › Part PART B— - COMMERCIAL › Chapter CHAPTER 311— - COMMERCIAL MOTOR VEHICLE SAFETY › Subchapter SUBCHAPTER II— - LENGTH AND WIDTH LIMITATIONS › § 31112
Stops states from letting long multi-trailer trucks run on the Interstate system and certain federal-aid primary highways unless those truck types were already allowed or already running in the state before June 2, 1991. A "property-carrying unit" means a trailer, semitrailer, or the cargo part of a single-unit truck (not the truck tractor). Length is measured from the front of the first cargo unit to the back of the last cargo unit. A state cannot permit combinations with more than one cargo unit that are longer than the maximum trailer length the state had by law or regulation before June 2, 1991, or longer than the lengths of combinations that were actually and lawfully operating there on a regular or seasonal basis before that date. A few specific exceptions are allowed for certain states. Wyoming can allow extra configurations authorized by its law by November 3, 1992, if they meet the axle and bridge rules in 23 U.S.C. 127(a) and weigh no more than 117,000 pounds. Ohio can allow three 28.5-foot cargo units on a 1-mile stretch of State Route 7 starting at and south of exit 16 of the Ohio Turnpike. Alaska can allow combinations that were running before July 6, 1991 but not on June 1, 1991. Iowa, Nebraska, Kansas, and Oregon have narrow, location- and use-specific allowances with precise length limits (for example, 81 feet 6 inches or 82 feet 8 inches) and crop- or harvester-only uses. Nebraska had a temporary sugar-beet rule that expired February 28, 1998. States must follow their June 1, 1991 rules to keep allowed vehicles running, may make minor temporary routing changes for safety, must notify the Secretary within 30 days of changes, and had to submit lists of their length limits by February 16, 1992. The Secretary had deadlines to publish and review those lists and to define “cannot be dismantled easily” and criteria for minor routing changes by June 15, 1992. The rule does not affect single-trailer trucks or combinations that were lawfully operating before June 2, 1991, and it does not override separate federal bans in 23 U.S.C. 127(d).
Full Legal Text
Transportation — Source: USLM XML via OLRC
Legislative History
Reference
Citation
49 U.S.C. § 31112
Title 49 — Transportation
Last Updated
Apr 6, 2026
Release point: 119-73