The Grumman Long Life Vehicle (LLV), also known as the Mailcat, is an American light transport truck model, designed as a mail truck for the United States Postal Service, which has been its primary user since it first entered service in 1986, 38 years ago. It was also used by Canada Post. The LLV uses a chassis built by GM based on the S-10 with an aluminum body built by Grumman.

A post van is a type of delivery vehicle that is used to transport post. Originally horse-drawn, most modern mail trucks are automotive vehicles.