Signs and Notices: Is an Old Ambulance Converted to a Utility Work Vehicle Considered a Truck

My question involves a traffic ticket from the state of: California

Recently, i was driving my F-450 heavy duty ambulance, that i converted to my daily utility truck. I was ticketed for driving my truck in a no truck zone. i was really curious to see if my car falls into the category of a truck or utility van. I had weighed the vehicle and it came out to be 9,600 pounds. Please if anyone can help me out with this, I'd really like some legal advice on it.

Thanks!

Signs and Notices: Is an Old Ambulance Converted to a Utility Work Vehicle Considered a Truck