La. Stat. tit. 32 § 387.8
Current with changes from the 2024 legislative session effective on or before 7/1/2024, from Acts 1-3, 6-671
All vehicles requiring a steering axle permit to travel on state highways shall also be entitled to travel on interstate highways without an additional permit, provided the single axle vehicles requiring such permit do not exceed twenty-four thousand pounds in weight.
La. R.S. § 32:387.8