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"
13'6"
50'
(1)
48'
Not Specified
(2)
20,000
34,000
80,000
State/Provincial Weight & Size Limits
Steering Axle
(lb.)
Single Axle
(lb.)
Tandem Axle
(lb.)
Gross Vehicle Weight
(lb.)
20,000
20,000
34,000
80,000
Width
Height
Straight Truck
Semi-Trailer
Full Trailer
Tractor &
Semi-Trailer
Tractor &
Semi-Trailer &
Full Trailer
Tractor & Triples
Other/Specials
102"
13'6"
40'
50'
(3)
Not Specified
Not Specified
(4)
Not Permitted
(5)
Not Permitted
Truck & Trailer:
75'
(1)  Measured from kingpin to end of trailer or load.  If trailer length exceeds 48', the distance from the kingpin to the center of the rear axle or group limited to 41'.  48' or shorter
trailers: no kingpin requirements.
(2)  Length of doubles not specified but trailers are limited to 28'6" each.
(3)  Trailers measuring 48' to 50' from kingpin to rear of trailer require a distance of 41' or less from kingpin to center of rear axle group.
(4)  But trailer may not exceed 50', or 41' axle group from kingpin to center of rear axle.
(5)  Allowed if both trailers are 28'6" or less.