1978 Mercedes-Benz 6.9 Sedan

Asking $16,900.00

Reasonable Offers Encouraged


Location: Indianapolis
VIN #:112-036-12-004006
Engine:6.9 L V8
Transmission:Auto
Wheelbase:116.5"
Power:286 HP
Mileage:125,204

The Mercedes-Benz 450SEL 6.9 is a high-performance version of the S-Class luxury saloon. It was built on its own assembly line by Daimler-Benz in Stuttgart, Germany and based on the long-wheelbase version of the W116 chassis introduced in 1972. The model was generally referred to in the company's literature as the "6.9", to separate it from the regular 450SEL.

The 6.9 was first shown to the motoring press at the Geneva Auto Show in 1974, and produced between 1975 and 1981 in extremely limited numbers. It was billed as the flagship of the Mercedes-Benz car line, and the successor to Mercedes-Benz's original high-performance sedan, the 300SEL 6.3. The 6.9 also has the distinction of being among the first vehicles ever produced with optional electronically-controlled anti-lock brakes, first introduced by Mercedes-Benz and Bosch in 1978. The 6.9's successor — the top of range 500 SEL — continued the 6.9's remarkable self-leveling hydropneumatic suspension as an extra-cost option. The 6.9 was the first Mercedes-Benz to be fitted with the company's new hydropneumatic self-levelling suspension system, unlike the 600 and 6.3 which employed air suspensions. The new system was similar to one developed by Citroën in 1955. Using a combination of fluid-filled struts and nitrogen-filled pressure vessels or "accumulators" in lieu of conventional shock absorbers and springs, the system was pressurized by a hydraulic pump driven by the engine's timing chain. Compared to the new Mercedes-Benz system, Citroën's was belt-driven, exactly like a conventional power steering pump; failure of the Citroën system thus might result in loss of suspension. Conversely, every unit of the 6.9 was shipped with hard rubber emergency dampers that served as temporary springs and allowed the car to be driven in the event of a hydraulic failure. The special hydraulic fluid required by the system was stored in a tank inside the engine compartment. Not only was the system totally self-adjusting, ride height could be altered by a dash-mounted push-pull knob under the speedometer that raised the car an additional two inches (50 mm) for increased ground clearance. NHTSA decreed this feature illegal in the US market, but it could be enabled simply by removing a limiter at the tank-mounted control valve.

The suspension system gave the 4200 pound car the benefits of a both a smooth ride and handling that allowed it, in the words of automotive journalist David E. Davis, to be "tossed about like a Mini." The car also featured a model W3B 050 three-speed automatic transmission unique to the 6.9 and a standard ZF limited slip differential both for enhanced roadholding performance on dry pavement and enhanced traction in inclement weather.

Four-wheel disc brakes and four-wheel independent suspension were standard across the W116 model range. The engine was a cast iron V8 with single overhead camshafts operating sodium-filled valves (as are found in piston-driven aircraft) against hardened valve seats on each aluminium alloy cylinder head. Each hand-built unit was bench-tested for 265 minutes, 40 of which were under full load. Bosch "K-Jetronic" electromechanical fuel injection was standard at a time when fuel-injected cars were uncommon. As in all Mercedes-Benz automobile engines, the crankshaft, connecting rods and pistons were forged instead of cast. In non-US trim, the 6.9 L power plant was conservatively rated at 286 hp with 405 ft·lbf of torque helping to compensate for the 2.65 to 1 final drive ratio necessary for sustained high-speed cruising.

Top speed was factory-rated at 140 mph, but some journalists testing the car saw speeds approaching 150 mph . Among those journalists was Brock Yates. Yates was approached by the factory to write promotional literature about the 6.9. He agreed, but under the condition that he could list the car's faults as well as its positives. Daimler-Benz agreed in turn, and Yates was given a US-spec 6.9 to drive from Manhattan to the Road Atlanta grand prix race track in Georgia. There, Yates would drive the car in as-arrived condition at racing speeds for a full 40 laps or just over 100 miles. The only change made to the car upon its arrival at Road Atlanta was the necessary adjustment of tire pressure. This was a difficult task even for a purpose-built race car, let alone a street-legal sedan designed and geared for high-speed Autobahn cruising. The 6.9 suffered no mechanical problems and averaged a very respectable 72 mph throughout the test, completing it with little more than excess dust on the bodywork from the Michelin radial street tires on which the car was driven to Atlanta. Yates was so comfortable driving the 6.9 around the track that he reported having run at least one lap with the sunroof open and the radio on, but the high price of the car made him think better of such risky driving and he finished the test with the radio off and both hands on the wheel

All of this technology came at a very high price. At a time when the most expensive Cadillacs, the mid-sized Seville and full-sized Fleetwood Series Seventy-Five limousine each listed for about $16,000, the 6.9 listed for around $40,000, more than most Rolls-Royces. When the car was officially introduced into the North American market for the 1977 model year, the price was well past $40,000 and was nearly $53,000 by the end of production.

This fine 2 owner example has been collector owned since 1985, and has been treated with respect and serviced properly by the dealer its entire life. The car is in excellent condition throughout. The paint, chrome, interior, and all rubber and plastic trim are all in excellent condition. The car runs very very well and everything works including the AC which blows Ice Cold. There is no rust or corrosion anywhere on the car which isn't surprising since the car has been properly garaged its entire life. Sporting new rubber this car is ready for your next cross country trip. If you are looking for a good Autobahn cruiser or executive express, this car is sure to provide years of driving pleasure and will reward your decision to purchase it with many miles of trouble free driving. Hey its AACA eligible too!

Sorry for the poor photography, I had the shutter open too far but I think you get the idea.

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