Simplify Your Oversize/Overweight Loads
Max Legal Weight for GVW under 80,000 lbs and Max Permitted Weight for GVW over 80,000 lbs
All size and weight limits imposed by Oklahoma Law are subject to the limitations of 23 U.S.C. 127 (imposing weight limitations on interstate travel of 20,000 pounds per Single Axle, 34,000 pounds per Tandem Axle and Gross Weight determined by formula, but not to exceed 80,000 pounds (except for designated routes of vehicles with Special Permits under State Law)). The following size and weight limitations have been adopted by the State of Oklahoma. In addition, local authorities may set size or weight limitations for highways under their jurisdiction. These limitations are to be indicated by the posting of signs on the applicable highways.
Source of information: https://www.ok.gov/dps/Administrative_Rules/Size_and_Weight_Permits/Size_and_Weight_Permit_Load/
http://okrules.elaws.us/oac/595:30-3-4
http://www.odot.org/title730/pdfs/730-30_proposed.pdf