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TruckingWikiRegulatory reference · Est. 2026
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50 jurisdictions verified
Front pageVehicle dimensions
TW-DIM
FEDERAL RULE · 23 CFR PART 658

Vehicle dimensions

Section 02✓ Sources verified23 CFR § 658.15TW-DIM

Federal law fixes the legal width of a commercial vehicle on the National Network and leaves height and length largely to the states. The width rule is unusual in that it is a ceiling and a floor at once — a state may impose neither more nor less than 102 inches.

1 Key rules

RuleRequirementAuthority
RequirementNo State shall impose a width limitation of more or less than 102 inches (2.6 metres / 102.36 inches) on a vehicle operating on the National Network. Hawaii is permitted to keep its 108-inch maximum under section 416(a) of the STAA.A ceiling and a floor simultaneously — a state may not set a stricter width limit than 102 inches either.§ 658.15(a)
Exemptions existYes§ 658.15(b)–(c)
ExemptionsSpecial mobile equipment as defined in § 658.5 is outside the width rule. Separately, a State may grant special use permits to vehicles exceeding 102 inches in width, including manufactured housing.§ 658.15(b), (c)

2 Sources

  1. Truck Size and Weight, Route Designations — Federal Highway Administration
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