§386. Weight
A. The total gross weight of any vehicle or combination of vehicles shall not exceed
eighty thousand pounds, and no vehicle or combination of vehicles shall exceed its licensed
gross weight.
B. No tire mounted on any axle attached to any vehicle or combination of vehicles
shall impose a greater weight on the surface of a highway than six hundred fifty pounds per
inch width of tire.
C. The total gross weight of any single axle attached to any vehicle and equipped
with low pressure pneumatic tires shall not exceed twenty thousand pounds.
D. The total gross weight of any tandem axle or tandem steering axle attached to any
vehicle and equipped with low pressure pneumatic tires shall not exceed thirty-four thousand
pounds. However on any vehicle carrying forest products in their natural state, the weight
limitation shall be thirty-seven thousand pounds per tandem axle and equipped with low
pressure pneumatic tires except on the Interstate system.
E.(1)The total gross weight of any tridum axle attached to any vehicle and equipped
with low pressure pneumatic tires shall not exceed forty-two thousand pounds.
(2) The total gross weight of any quadrum axle attached to any vehicle and equipped
with low pressure pneumatic tires shall not exceed fifty thousand pounds.
F. The total gross weight of any single axle or any single steering axle attached to
any vehicle and equipped with high pressure pneumatic, solid rubber or cushion tires shall
not exceed eighteen thousand pounds.
G. The total gross weight of any tandem axle or any tandem steering axle attached
to any vehicle and equipped with high pressure pneumatic, solid rubber or cushion tires shall
not exceed thirty-two thousand pounds.
H.(1) For vehicles using the Interstate system, the overall maximum gross weight,
including enforcement tolerances, on a group of two or more consecutive axles, shall be
produced by application of the following formula:
W = 500(LN/(N - 1) + 12N + 36)
where W equals overall gross weight on any group of two or more consecutive axles to the
nearest five hundred pounds, L equals distance in feet between the extreme of any group of
two or more consecutive axles, and N equals number of axles in group under consideration,
except that two consecutive sets of tandem axles may carry a gross load of thirty-four
thousand pounds each provided the overall distance between the first and last axles of the
consecutive sets of tandem axles is thirty-six feet or more. The overall gross weight shall not
exceed eighty thousand pounds, including all enforcement tolerances, except for those
vehicles and loads which cannot be easily dismantled or divided and which have been issued
special permits.
(2) In accordance with 23 U.S.C.A. 127, certain vehicles carrying certain
commodities shall be exempt from application of the formula. The exemptions shall include
the following:
Vehicles with Type Two axle configuration (three axle combination with one single
axle and one set of tandem axles); or Type Six axle configuration (five axle combination
with one single axle and two sets of tandem axles); or a vehicle with Type Eight axle
configuration (six axle combination with one single axle, one tandem axle, and one tridem
axle); or vehicles with Type Ten axle configuration (double bottom); or Type Eighteen axle
configuration (four axle combination with one single axle and one set of tridem axles)
carrying any of the following bulk commodities thereof: forest products in their natural state,
lumber, sand, gravel, agricultural products in their natural state, loose or mixed concrete
(including asphaltic or Portland cement), or bulk liquid commodities.
(3) All vehicles which are rendered economically useless by application of the bridge
formula which are legal and operational on the effective date of this Subsection shall remain
legal for a period of five years from the effective date of this Subsection. The trucking
industry is hereby granted a phase-in period to extend for a period of five years from the
effective date of this Subsection, within which time it shall adjust, modify, or replace
equipment to comply with the provisions of this Subsection.
I. Notwithstanding the provisions of Subsection (A) of this Section and subject to
the provisions of Subsections B, C, D, and E of this Section, the total gross weight of any
combination of vehicles which has a tridum axle or a quadrum axle shall not exceed eighty-eight thousand pounds while operating on any state-maintained highway except the Interstate
System and shall not exceed eighty-three thousand four hundred pounds while operating on
the Interstate System within this state.
J. When by reason of the condition of the weather or other emergency, or the
physical condition of any highway or its recent construction, or the making of repairs thereto,
the secretary deems it necessary, then for such time as is reasonably necessary to remedy the
situation, he may prohibit the use of such highway or specify lesser gross weights than those
fixed in this Section, pursuant to the recommendations of the chief engineer of the
department, in order to protect the public highways and the persons and property of the
traveling public from unnecessary damage. Notice of such restrictions, prohibitions, or
weight reductions shall be given by the secretary by posters at the terminal of the highway.
However, failure to post such notice shall under no circumstances make either the state or
the department liable for damages which may result because of such failure.
K. Vehicles and combinations of vehicles shall be loaded in such manner that the
axle limitations set forth in Subsections C, D, E, F, and G of this Section are not exceeded.
However, while operating on any state-maintained highway except the Interstate System, the
provisions of Subsections C, D, E, F, and G of this Section shall not be deemed to have been
violated unless the axle weight exceeds by more than two thousand pounds Subsections C
and F of this section or more than three thousand pounds Subsections D, E, and G of this
Section. This Subsection shall in no way be construed to allow the total gross weight in any
vehicle or combination of vehicles to exceed the gross weight limits set forth in Subsection
A or I of this Section.
L.(1) Notwithstanding any provision of law to the contrary, a vehicle that is operated
by an engine fueled primarily by compressed or liquified natural gas may exceed the gross
vehicle weight limits and any axle weight limits imposed by this Section by an amount, not
to exceed a maximum of two thousand pounds, that is equal to the difference between the
weight of the vehicle attributable to the natural gas tank and fueling system carried by the
vehicle and the weight of a comparable diesel tank and fueling system.
(2) The weight exception provided in this Subsection shall apply to all state roads
and interstate highways per the exemption expressly permitted by 23 U.S.C. 127, as amended
by Section 1410 of the Fixing America's Surface Transportation Act of 2015.
Acts 1977, No. 113, §1, eff. June 22, 1977. Amended by Acts 1978, No. 35, §1, eff.
May 31, 1978; Acts 1982, No. 196, §1; Acts 1987, No. 686, §1; Acts 2016, No. 279, §1.
{{NOTE: SEE ACTS 1987, NO. 686, §2 FOR RULEMAKING
AUTHORITY.}}