The American Driver
From Drivers...For Drivers
National Weight & Size Provisions
Width
Height
Semi-Trailer in
Tractor-Semi-Trailer Combo
Full Trailer
Doubles
Single Axle
(lb.)
Tandem Axle
(lb.)
Gross Vehicle Weight
(lb.)
102"
14'0"
53'
53'
Not Specified (1)
20,000
34,000
80,000 (2)
State/Provincial Weight & Size Limits
Steering Axle
(lb.)
Single Axle
(lb.)
Tandem Axle
(lb.)
Gross Vehicle Weight
(lb.)
20,000 (3)
20,000
37,800 (4)
105,500 (2)
Width
Height
Straight Truck
Semi-Trailer
Full Trailer
Tractor &
Semi-Trailer
Tractor &
Semi-Trailer &
Full Trailer
Tractor & Triples
Other/Specials
102"
14'0"
45'
48'
53' on some highways
48'
53' on some highways
75' unless
otherwise
specified
(5)
(6)
Not Specified (7)
(1) Overall length is 68' for the trailing units including space between.
(2) Permit needed to exceed 80,000 lbs. up to 105,500 lbs.
(3) 20,000 lbs. or 600 lb./inch width of tire, whichever is more restrictive.
(4) When not over 80,000 lbs.
(5) 68' of trailers (including space in between) allowed on National Network roads.  61' of trailers (including space in between), or 75' overall, allowed on non-National Network roads.
(6) Allowed on Interstate and state-designated routes with Extra-length permit.
(7) Seasonal weight limits on non-designated routes are variable -- approx. Feb to May.  Information on highways under Frost Law available by calling 208-334-8420 and at first Port of
Entry.