The current United States Postal Service mail truck fleet is ancient. Older than some of the people driving the vehicles. It’s long past due for an upgrade with some basics like air conditioning and a clock, and thankfully USPS just announced OshKosh Defense will make the next mail truck. And among its many upgrades is the option for a fully electric vehicle.
Source: The New USPS Mail Truck is Sleek, Modern, and Potentially Electric – Review Geek