Maximum Legal Weight Allowed
|Gross Vehicle Weight
|80,000 pounds (except that freight motor vehicles operating on interstate highway system shall not exceed the lesser of 80,000 pounds or the weight produced by application of the formula set in T.C.A.)
Maximum Permit Weight Allowed
Conditions for Permitting Overweight Movements
In general, the maximum allowable axle weights by special permit are as follows:
- Single Axle: 20,000 pounds;
- Tandem Axle: 40,000 pounds; and
- In no case shall a single axle in a tandem group exceed 20,000 pounds.
However, a special permit for the movement of a non-divisible load may be issued for axle weights exceeding the maximum axle weights established above, subject to the following conditions:
- The maximum width of the vehicle, including the truck and semi-trailer or trailer combination, shall not exceed 10’; provided, however, the load may exceed 10’ if properly permitted;
- No single axle shall carry a load in excess of 23,000 pounds;
- No tandem axle group shall carry a load in excess of 46,000 pounds; and
- No axle group of 3 axles (tridem) shall carry a load in excess of 60,000 pounds.
Any movements with a gross weight exceeding 165,000 pounds may only be permitted, as provided in Rule 1680-07-01-.12 or Rule 1680-07-01-.19, if the movement is not detrimental or unsafe to the traveling public and the highway can accommodate the movement. In addition, such movements must be approved by the TDOT Structures Division before a special permit may be issued. Some movements with a gross weight of less than 165,000 pounds may also be subject to the prior approval of the TDOT Structures Division based on the axle spacing of the vehicle carrying the load.
Movement of super heavy and/or extra-overdimensional loads may be permitted provided the highway can accommodate the move and the move is not considered to be detrimental or unsafe for the other traveling public. For the purposes of this rule, “super heavy” means that the total gross weight of the vehicle and load exceeds 165,000 pounds, and “extra-overdimensional” means that the width of the vehicle and load exceeds 16’ or the height of the vehicle and load exceeds 15’6”.