What is the primary reason registration papers are required to be kept with trucks at all times?

The requirement to keep registration papers with trucks at all times primarily serves to show the weight of the truck when it's empty and its registered hauling capacity. This information is crucial for compliance with weight regulations and safety standards on the road. Law enforcement and regulatory agencies need to verify that the truck adheres to legal weight limits for transport, which can vary based on the type of cargo and the vehicle itself.

While proving ownership, verifying the driver’s identity, and providing insurance information are important functions of registration papers, the immediate concern with having these documents on hand primarily relates to ensuring that the truck is being operated within its legal limits concerning weight and capacity. This ensures not only the safety of the vehicle but also protects public roads from damage due to overweight vehicles.