Before getting the rental car of your selected budget Tucson car rental, you should be informed of a number of important traffic laws. It is illegal to use a cell phone as you drive in Tucson. Tucson drivers must always adhere to the established speed restrictions on designated roads. It is advisable that you follow the overall speed limits specified by the highway authorities when operating your rental car on highways without clearly visible speed limit signs. When driving in Tucson on any unpaved roads, keep your speed to 30-35 mph or less. In school zones in Tucson, 2-250 mph is the top speed limit. The main prerequisite is that all renter car drivers follow the 70 mph upper speed limit on Tucson's rural interstates.