Final answer:
The maximum length allowed for a single motor vehicle other than a truck tractor varies by state and is subject to specific state laws.
Step-by-step explanation:
The greatest length allowed by State law for a single motor vehicle other than a truck tractor varies from state to state. The maximum length permitted is typically determined based on the type of vehicle and its purpose of use. For example, in some states, the maximum length is 40 feet for a single vehicle, while in other states it may be 45 or 48 feet.
However, it is important to note that this information may change over time, so it is always best to refer to the specific state law or consult with legal authorities for the most up-to-date information.