W. Va. Code § 17C-17-8: Single-axle load limit.

(a) The gross weight imposed on the highway by the wheels of any one axle of a vehicle shall not exceed twenty thousand pounds.

(b) For the purpose of this article an axle load shall be defined as the total load transmitted to the road by all wheels whose centers are included between two parallel transverse vertical planes forty inches apart, extending across the full width of the vehicle.