Apart from German and other governments and the Pope, famous owners of the 600 include numerous celebrities (Hugh Hefner, Elizabeth Taylor, John Lennon, Jason Kay, Aristotle Onassis, Jack Nicholson, Hirohito, Simon Spies, Bob Jane, Elvis Presley, Rowan Atkinson, Jeremy Clarkson), Communist rulers (Nicolae Ceau?escu, Josip Broz-Tito, Mao Zedong, Fidel Castro, Pol Pot, Enver Hoxha, Leonid Brezhnev, Kim il Sung), a religious leader (Guru Maharaj Ji), and African revolutionaries (Idi Amin Dada, Jomo Kenyatta)
The model came in two main variants:
* short wheelbase
o 4-door sedan, similar to a modern S600 sedan in layout.
o 4-door sedan, but with a power divider window separating the front seats from the rear bench seat.
* long wheelbase chassis Pullman
o 4-door limousine, featuring additional two rear-facing seats behind the driver compartment which was separated by a power divider window (in all but three built)
o 6-door limousine, with two forward facing jump seats stationed at the additional middle two doors and a rear bench seat.
* A few of the limousines were made with a convertible top over the rear passenger compartment and were called landaulets. This was mainly intended for government use, by the Pope, or by the German government, e.g. in 1965 during the visit of Queen Elizabeth II, when she was accompanied by Kurt Georg Kiesinger in open-top tour in Baden-Württemberg. Production of this model ended a year early, in 1971.
Mercedes made two coupés, one of them as a gift for Dr. Rudolf Uhlenhaut when he retired. He had designed the car, together with Fritz Nallinger and Karl Wilfert. A third coupe was constructed from a 600 SWB by Karl Middelhauve and associates.
Some companies altered the car, according to wishes of customers. A funeral coach (hearse) was made from an SWB car. This car, and the two coupés mentioned above, survive to the present day in the United States.
The 600 was so heavy that the largest engine of Mercedes at that time, the 6-cylinder 300, was inadequate. Instead a new engine with more than twice the capacity was specially developed to move the vehicle and its hydraulically powered amenities, the massive 6.3L V8 "M100" engine with single overhead camshafts, dry sump and Bosch mechanical fuel injection. Adjustable air suspension gave the car a smooth ride and good handling over any road surface. Although the car's agility was inevitably compromised by its mass, the top end speed still was only equalled by the new Porsche 911.
Produced from 1964 to until 1981 in low numbers, this model had no equal in the Mercedes-Benz lineup until the introduction of the modern Maybach 57 and 62 models.
The 600's "M-100" engine and air suspension were fitted to the 300SEL 6.3 model in 1968, providing the lighter (and more affordable) car with more competent propulsion. Upon the introduction of the "W116" chassis, a larger version of the M-100 was installed in the limited-production Mercedes-Benz 450SEL 6.9.