Wis. Admin. Code Trans § Trans 276.06
For enforcement purposes, no permit is required for vehicles operating in double or triple saddlemount combination provided the overall length of the combination is 75 feet or less, or for the operation of any motor bus provided the overall length of the motor bus is 45 feet or less. This section applies to the national network and access routes.
Note: The provision of Wisconsin law requiring a permit for these combinations (s. 348.27(13), Stats., was preempted by the federal rule (23 CFR 658.13(d) (1) iii.) when these vehicles operate on the designated system and access routes.
The provision of Wisconsin law requiring a permit for the operation of motor buses in excess of 40 feet in length (s. 348.07(1), Stats.) was preempted by federal law (49 USC Appx. section 2311 (a) as amended by section 4006 (b) of the Intermodal Surface Transportation Efficiency Act of 1991) when these vehicles operate on the federally designated system and access routes.
Wis. Admin. Code Department of Transportation Trans 276.06