First introduced to the public at the 1951 Frankfurt
Motor Show, the 300 is important in the post war Mercedes
line-up as it represents the return by Mercedes to manufacturing
outstanding high quality and luxurious automobiles.
With a maximum cruising speed in excess of 160 km/h
(100mph) the car was powered by a 6 cylinder 3 liter
overhead cam engine with a seven bearing crankshaft.
While many aspects of the car were carried over from the
170 series, the 300 had such improvements as a new steering
mechanism, hypoid bevel final drive and dynamically balanced
The short stroke engine used a special valve arrangement and combustion chamber design combined with a thermostatically controlled water circulation and oil temperature, making the M186 engine at the time arguably the most robust and quiet ever manufactured.
The chassis incorporated all of the features of the 170S plus a number of additional refinements, such as a new steering mechanism design, electrical control of the rear suspension to allow the driver to adjust for different carrying loads. All up, the 300 was without peer.
The 300 sedan was built from November 1951 until March 1954, however it was also available in cabriolet form (pre-series production in April 1951 with regular production from March 1952).
The Type 300b was built from March 1954 until August 1955, and boasted a more powerful engine, power now up at 125 hp, and better brakes. The 300c followed, and although it retained the standard transmission, it was fitted with two compound carburetors, higher compression and a better axle ratio, its production run spanning September 1955 through July 1957. The Cabriolet D was available in July 1956, it being built to special order on a 3150mm wheelbase, and having a rather large for the time 5165mm body length.
The final iteration was the 300d, which had a slightly modernised body and fuel injected engine; it remained in production until March 1962. Any 300 model today is highly collectible, however
as with all models (regardless of manufacturer) the
convertible models will demand the highest prices.
There is also much beauty in the "bright-work" incorporated
into the 300 sedans manufactured after 1957.