The bodies had been slightly revised from the 1929 Series 65. For example, there were bowl-shaped headlights instead of the heavier barrel and fenders.
From the middle of the model year, a larger engine was used, drawing from 3582 cc engine 75 hp (55 kW). These models were built also in 1931, the Series 66 was built with 22,606 vehicles being produced during that time.
In the model year 1931 the Series 66 was replaced with the revised Chrysler Series CM.