White Brothers #893 General American Milk Car From the detailed underframe to the sprung buffers to the plated interior tanks and piping, Lionel General American Milk Cars have raised the bar for O gauge rolling stock. Each of the previous released liveries is now available in two new road numbers. Built in the early 1900s, milk cars frequently ran along passenger routes to get their perishable cargo to market as quickly as possible. The wooden milk cars were a fixture on many railroads until the 1950s.