Auto body repair & detailing: Glossy Fleet Paint, fleet finishes, urethane

Question
good day
noticed that some paints used on vehicles ie. trucks, cranes, cars etc... keep a gloss looking shine even when the vehicles are dirty.
For example, close to where I live there is a company that has a fleet of trucks and even though the trucks are dirty with dust etc. (when noticed from close up) the trucks still look clean and shiny (glossy) from more than 8 feet.
I believe that it is due to the paint, additives, and maybe coatings.
Wanted to find out what type(s) of paint, additives and coatings are used to achieve this effect.

Answer
Hi Sam,

They typically use a high quality urethane or polyurethane finish. These type paints are known for their extreme gloss. I would recommend something like PPG's Delfleet FDGH or FDGU. These finishes are specifically designed for fleets such as 18 wheelers, dump trucks, concrete trucks, cranes etc...