Size and Weight Information



Interstate (I-70, I-25, I-76)


Single Axle Limit


20,000 lbs

20,000 lbs

Tandem Axle Limit

36,000 lbs

40,000 lbs

Gross Weight Limit

80,000 lbs
(Subject to Federal Bridge Weight Formula)

85,000 lbs
(Subject to State Bridge Weight Formula)

Note: Triple Axles (or more) do not have a defined limit but the vehicle(s) still cannot exceed gross weight limits.


Gross Weight

The maximum gross weight is determined by finding the maximum bridge weight for the unit or combination that can be found here:

  • Federal Bridge Weight Calculator
Federal Bridge Weight Formula

W = 500 [LN/N-1 + 12N + 36]

W = the overall gross weight on any group of two or more consecutive axles to the nearest 500 pounds.

L = the distance in feet between the outer axles of any group of two or more consecutive axles.

N = the number of axles in the group under consideration.

  • State Bridge Weight Formula
    • Weight=1000(Length+40)