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This article was first published in 2002.
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The legendary Silver Arrows were not the only vehicles that were the talk of the town in the early nineteen-fifties. The Mercedes-Benz racing department also hit the headlines off the racetracks, with its "fastest racing car transporter in the world".
In 1952 the board of management of Daimler-Benz decided that in two years time, 1954, it would return to Grand Prix racing. The company's racing department, which had already set up the extremely successful 300 SL racing sports cars in 1952, set out to translate the plans for a Grand Prix car - internally designated W 196 - into reality.
Parallel to this, it was, of course, essential to equip a workshop vehicle for servicing and repairs alongside the racetrack, and to build a truck for transporting the racing cars. Team chief Neubauer couldn't get the idea of a fast racing car transporter out of his mind. The idea was presented to master craftsman Hägele, with the final words of encouragement being: "Come up with something good!"
Hägele was in charge of a test department in which chassis and running gear technicians, engine specialists and bodymakers produced prototypes. The demands made on the transporter were specified easily enough: it was to be fast - very fast even when laden with a Grand Prix car or SLR racing sports car. It therefore had to have plenty of power and equally powerful brakes.
It is no longer possible to retrace the individual steps in the production of the racing car transporter in every detail, but it is known that the vehicle was a joint development of Hägele's team.
Engineer Hennige finally suggested the combination of the X-shaped tubular frame from the 300 S, the high performance engine from the 300 SL and interior fittings from the 180. Rudolf Uhlenhaut gave the green light and the team set out to tackle the work.
Design
The designers of the racing car transporter succeeded in achieving the impossible: they created a truly unique car in terms of both looks and technical perfection. And they provided the racing deparment with exactly what the latter needed: an incomparably fast vehicle for transporting racing cars.
The X-shaped tubular frame of the 300 S was extended at the front and rear to provide ample space for a Mercedes-Benz racing car on the load platform. The direct-injection SL engine was installed just above the front axle. A synchronized four-speed transmission with involute profiles and a Daimler-Benz single-plate dry clutch were both flanged to the engine.
At the front, a double wishbone axle with coil springs and Fichtel & Sachs shock absorbers was installed. At the rear could be found a swing axle with a hypoid crown wheel and pinion assembly, lowered and separate pivot points for the two axle carriers, coil springs, an additional torsion bar spring and also F & S shock absorbers. At 3050mm, the wheel-base was impressively long.
Hydraulic drum brakes on all four wheels and a pneumatic brake booster from Bosch reliably decelerated the vehicle whose laden weight was just under 3000kg.
Safety was further enhanced by a disc brake installed between propeller shaft and differential as well as by an exhaust brake - a new feature on a passenger car engine. The engine itself was very special: in view of the heavy-duty work lying ahead of it, the output of the original three-litre six-cylinder in-line engine from the 300 SL was reduced from 215 to 192hp. With this output and its high torque, this engine easily gave the racing car transporter a top speed of 160 - 170 km/h!
All of these components vanished underneath a sheet metal skin that served as an all-time memorial to the imagination, creativity, commitment and skills of the bodymakers. Experts realize immediately that the centre section of the driver's cab - from the windshield to the rear edge of the door - was adopted from the 180 production model, only that everything was much wider. The front end, set at a steep angle and rounded, flowed into an SL-type coolant-air intake with a Mercedes star right in the centre. The front end's rounded contours were delineated at the sides by rudimentary fenders, unmistakable features of the 180, with integrated headlights and fog lights, and at the front by a sweeping chrome bumper, with large bumper guards, wrapping around the corners of the cab.
The engineers succeeded in creating a technical masterpiece, a unique vehicle whose origins were easy to identify. No matter what you looked at, the bodywork, the engine or the frame, the racing car transporter was unmistakably a Mercedes. From roughly the upper seat edge level, the rear section of the cab bulged outwards towards the rear, to taper towards the centre. Rear glass screens curved at two levels testified to the proud achievements of the glazing artists. The front end of an SLR or Formula One car fitted underneath this nose-like shape like a hand in a glove.
Behind the cab mounted in a low position and ahead of the front axle, the transport section of this remarkable vehicle began - as avantgarde as everything else on this transporter. The frame, engine, radiator, axles and fuel tank all vanished under complete panelling. The front and rear fenders elegantly extended far towards the rear, enclosing the wheels in an aerodynamically efficient manner. With their flowing lines, they unobtrusively integrated the load and its carrier into an entity. The front and rear fenders were linked by inward-curving panelling flowing into the load platform. The recessed space between the axles accommodated a spare wheel on each side, fixed at an angle and quickly retrievable when required.
A very clever idea was integrated in that tripods were firmly mounted on the spare wheel hub caps. These elements served as supports for the U-shaped two-part access rails for the racing car which was strapped down by steel ropes on the load platform, its wheels resting in firmly installed upward-curving rails. The access rails were accommodated in a well-secured position between the wheel recesses during transport.
The fully panelled rear end was reminiscent of the 300 SLR, indicating the vehicle's purpose from this perspective as well. The rear was, of course, also trimmed with a single-part chrome bumper since the vehicle's creators felt that their design was a passenger car more than anything else, albeit one for the special purpose of transporting a racing car.
So there it was, in mid-1954, being 6750mm long, 2000mm wide, just 1750mm high: a dynamic appearance expressing power, wrapped in extravagant bodywork that was, of course, painted in Mercedes-Benz blue.
A vehicle with a "storming-ahead" appeal, ready to go and looking fast even when stationary.
A retired member of staff remembers, "For us in the racing department, this vehicle was a blessing. We often had a few more hours to complete the setup or the last modifications on a racing car with greater care and less pressure. By the same token, a damaged or defective car was returned to us more quickly, giving us more time for repairs. After every race, the cars were dismantled and checked, defective parts were replaced, repaired or modified and adapted to the relevant driver."
The racing car transporter was a sensation on European roads and motorways during its active time from mid-1954 until the fall of 1955, when Daimler-Benz withdrew from racing again. The vehicle even became a star in the paddocks, where it often attracted larger crowds than the racing cars.
The 300 SLR and its transporter were shipped across the Atlantic and caused quite a sensation at every one of the exhibitions at which the combination was displayed. Legends were woven around the combination's top speed until someone painted "Max. Speed 105 m.p.h." on its rear fenders. This put a stop to the questions, but not to people's amazement. In late 1957, the fast transporter returned to home ground, slightly the worse for wear but still in good condition overall.
The Mercedes-Benz Museum was to become the final place of rest for the aging but still fascinating transporter - together with a 300 SLR already waiting for it.
However, the team of transporter and racing sports car proved to be too heavy for the old museum's floors. Plans to reconstruct the museum further prevented the combination from being displayed. And so it happened that the once proud racing car transporter had to do duty in the testing department until it was beyond repair and finally scrapped at Rudolf Uhlenhaut's command in December 1967.
Comeback
The manufacture of the racing car transporter had already been a bold and visionary project in its "first life"; this was almost topped by the plan to reconstruct this witness to Mercedes-Benz motor sport history. Since there were hardly any drawings or documents relating to the racing car transporter's design, the relevant specifications had to be compiled in scrupulously detailed work.
Extensive research within the company finally revealed that there were only a few records on this vehicle to be found in the Corporate Archives and contemporaries' documents.
A great help proved to be staff reports on what happened at the time. In this way, important facts were re-established, photos obtained and many details brought back into the light of day. Design drawings, however, were simply non-existent. Like so many other one-off cars at Daimler-Benz, the racing car transporter had been built without any design drawings being used.
Finally, in 1993, Messrs MIKA GmbH in Mölln in the north of Germany, specialists in the restoration of motor vehicles, were given the task by the Mercedes-Benz Museum to rebuild the racing car transporter in true-to-the-original style based upon photos and data available - a challenge they mastered. Almost 6000 working hours were spent on redesigning and building the racing car transporter. This meant seven years of fiddling, of elaborating the steering and gearshift geometries, of designing the cable harness, of manufacturing the cab's rear windows and all the details to be found under the sheet metal skin.
For safety reasons, a small deviation from the original was approved: the front wheels are equipped with 1989 SL disc brakes, and the disc brake between propeller shaft and differential was omitted. All other technical data and features like engine output, axle configuration, transmission spacing, exterior dimensions, bucket-type seats complete with upholstery fabrics, the location of the rev counter, the dimensions of the access rails, etc. are precisely the same as on the original transporter.
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