State Oversize Permits & Escorts Information

Length:

• 53′ semi-trailer on National Network
• 48′ trailer on non-N.N. (“non-designated”)

Note: Several two-lane highways in Idaho are non-designated, including US-12 except in the Lewiston to Spalding, US-93 from Salmon to Challis, and US-95 from Council to Grangeville.

• Divisible loads, trailers exceeding 48’ are only allowed with an annual extra length permit, and the tractor-trailer off-track measurement must not exceed 5.50 feet (3.00 on a few mountain routes)
• Non-divisible loads are covered by single or annual permit, without regard to off-track amount.

Overhang: 4′ front, 15′ rear

Width: 8′-6″

Height: 14′

Weight: 80,000 Gross

• Single – 20,000
• Tandem – 34,000
• Tridem – depends on spacings
• Steer – 600 pounds per inch of tread width (13,200 pounds with 11″ tires)

Divisible Loads Exceeding 80,000: You can exceed 80,000 gross without a permit on state highways as long as you are legal on all axle/group weights and you are licensed for at least the amount of your gross weight. However, if you need any Interstate routes, you will need to get an Annual Excess Weight Permit.

‍

Length: 110′

Width: 16′

Height: 15′-6″

Weight:

• Single – 33,000 to 22,000*
• Tandem – 56,000 to 38,500*
• Tridem – 70,500 to 48,000*
• Steer – 600 pounds per inch of tread width (13,200 pounds for 11″ tires)

* Group weight maximums depend on route classification, with Interstate routes getting the highest.

Loads exceeding these dimensions or are considered as Super Loads.

‍