The W186 Type 300 'Adenauer' saloon, was launched at the 1951 Paris Salon. The 300 was not entirely new as its X-frame chassis was carried over from pre-War models. A new 2996cc ohc 6-cylinder engine with twin carbs gave the 300 113bhp. The same engine was given a new head and triple carbs to power the 300 SL gullwing model. There were two factory bodystyles, the 6-passenger saloon or the cabriolet. In 1954 the W186 III was given front vent windows and power brakes and is known as the 300b. In 1955 the 300c gained a larger rear window and automatic transmission became an option. Production ended in 1957. It is known as the 'Adenauer' because German Chancellor Dr. Konrad Adenauer owned six of these whilst he was in office.
The engine from the 300 was developed for use in the 300 SL gullwing and roadster