This from Keith Grzadziel:

In the back row, far right, you can see the 1949 Oshkosh/Howe with its very distinctive thru the hood chrome exhaust stack. 

At the time of annexation from Grandview Park FPD, Oak Lawn FD took possession of their station and fleet. This became Oak Lawn Engine 3.

Photo courtesy of the Oak Lawn Public Library; #OakLawnFD; #historicphoto;

Photo from the Oak Park Public Library