How big an issue is weight?

Crowe wrote:
Can you tell what law makes it a crime to pull a non-commercial overweight RV?

Reckless Endangerment. Definition:

Reckless endangerment is a crime consisting of acts that create a substantial risk of serious physical injury to another person. The accused person isn't required to intend the resulting or potential harm, but must have acted in a way that showed a disregard for the foreseeable consequences of the actions. The charge may occur in various contexts, such as, among others, domestic cases, car accidents, construction site accidents, testing sites, domestic/child abuse situations, and hospital abuse. State laws and penalties vary, so local laws should be consulted.

Better re-read my question, that says nothing about an RV being overweight. So I will presume you couldn't find anything and that was the best you could come up with (which could also apply to slipping on a banana peel).