It’s not clear to me whether this was part of a fire department or just made to look like that. The seller is firefighter.

https://portland.craigslist.org/clc/cto/d/mount-angel-1947-willys-jeep/7266972623.html

“I’m a firefighter and it’s time to sell my “fleet”. The fire trucks have been sold but this 1947 Willys is a solid runner. Top and bottom of original engine has been rebuilt. New radiator installed last September. Has Warn hubs and like new Toyo tires. In addition to four wheel drive the overdrive allows you to drive comfortably at 50-55 mph, Tow bar will be included. Emergency lights have been removed.”