(a) Minimum axle group spacing. For an axle group to be permitted for maximum weight authorized under this section:      
        (1) an axle group must have a minimum spacing of four feet, measured from center of axle to center of axle, between each axle in the group; and       
        (2) two or more consecutive axle groups must have a minimum axle spacing of 12 feet, measured from center of the last axle of a group to center of the first axle of the immediately following group.       
      (b) Maximum permit weight. Maximum permit weight for an axle or axle group is the weight computed by multiplying 650 pounds times the total number of inches of the width of tires on the axle or group or the following applicable axle or axle group weight, whichever is less:      
        (1) single axle - 25,000 pounds;       
        (2) two-axle group - 46,000 pounds;       
        (3) three-axle group - 60,000 pounds;       
        (4) four-axle group - 70,000 pounds;       
        (5) five-axle group - 81,400 pounds; or       
        (6) trunnion axles - 60,000 pounds if:                  (A) the trunnion configuration has two axles;                   (B) there are a total of 16 tires for the trunnion configuration; and                   (C) the trunnion axle, as shown in the following diagram, is 10 feet in width.          
            Attached Graphic           
      (c) Tire load rating. A permit issued under this subchapter does not authorize the vehicle to exceed manufacturer's tire load rating.     
      (d) Permits for vehicles exceeding permit weight limits. For a vehicle exceeding weight limits provided in this section, a person must apply directly to the Texas Department of Motor Vehicles for an oversize or overweight permit in accordance with Transportation Code, Chapter 623.     
     Source Note:        The provisions of this §28.115 adopted to be effective November 17, 2016, 41 TexReg 9026