# Mercedes-Benz W116

The Mercedes-Benz W116 is a series of flagship luxury sedans produced from September 1972 until 1980. The W116 automobiles were the first Mercedes-Benz models to be officially called S-Class, although some earlier sedan models had already been designated unofficially with the letter 'S' for Sonderklasse (German for 'special class'). The W116 was selected as European Car of the Year in 1974.

## History

The W116's development began in 1966, which was only a year after the launch of the W108/09. This was the first Mercedes-Benz sedan to feature the brand-new corporate styling theme, which endured until 1993, when the 190 was discontinued. The design, finalized in December 1969, was a dramatic leap forward, with more masculine lines that combined to create an elegant and sporty character. The basic design concept continued the themes originally introduced on the R107 SL-Class roadster, especially the front and rear lights. As with the SL, the W116 received the ridged lamp covers which kept dirt accumulation at bay; this was to remain a Mercedes-Benz design theme into the 21st century. The W116 was Friedrich Geiger's last design for Mercedes-Benz; his career had started with the Mercedes-Benz 500K in 1933.
The W116 was presented in September 1972. The model range initially included two versions of the M110 engine (straight-six with 2746 cc displacement) — the 280S (using a Solex carburetor) and the 280SE (using Bosch D-Jetronic injection), plus the 350SE, powered by the M116 engine (V8 with 3499 cc displacement). After the 1973 oil crisis, a long-wheelbase 280SEL was added to the model range.
The larger 4.5-litre M117 V8 engines were developed in response to US emission regulations and initially fitted to the 350SL and 350SLC for the US market in 1972, which were renamed as the 450SL and 450SLC in 1973. Mercedes-Benz introduced the 450SE and 450SEL for both US and international markets in 1973. The 4.5-litre models were available with three-speed automatic gearboxes only, while the models with smaller 3.5-litre V8 engine could be ordered with a four-speed (and later five-speed) manual gearbox. The 450SE and 450SEL received a plusher interior, with velour or leather seats rather than the checkered cloth of the lesser models. The door cards had the velour or leather inserts.
The 4.5-litre M117 V8 engines had 225 PS (165 kW) in most European and international markets, 190 hp (142 kW) for the US market, and 200 PS (147 kW) for Swedish and Australian markets. The 450 models received a plusher interior as well, with velour or leather seats rather than the checkered cloth of the lesser models. The door cards were also of a different design, with pads being pulled up around the windows.
The W116 had independent suspension and disk brakes on all four wheels.
The most notable W116 model was the high-performance, limited-production 450SEL 6.9, which was introduced in 1975. This model boasted the largest engine installed in a post-war Mercedes-Benz (and any non-American production automobile) up to that time, and it also featured self-leveling hydropneumatic suspension.
Exclusive to the North American and Japanese markets was the 300SD, the world's first passenger car with a turbocharged diesel engine, which was introduced in 1978. No 300SD model was offered in Europe (where diesel engines were well-received and had tax advantages) until 1991, when the W140 300SD was finally introduced in Europe and international markets.
The 450SE was named the European Car of the Year in 1974, even though the W116 range was first introduced at the Paris Motor Show in the fall of 1972. The W116 became the first production car to use an electronic four-wheel multi-channel anti-lock braking system (ABS) from Bosch as an option from 1978 on.
Production totaled 473,035 units. The W116 was succeeded by the W126 S-Class in 1979. The W116 was sold throughout Europe, the Americas, Asia, the Middle East, Africa, and Australia.

## Fuel injection

In 1975, the W116 was upgraded with a new fuel injection system to comply with revised exhaust emission standards in European markets. A slight power reduction was a result of this update. In 1978, a series of engine upgrades restored original performance levels with new fuel injection systems. The early models (1973-1974) of the W116 with the twin cam inline 6 used the D-Jetronic fuel injection system with computers and MAP sensor that are both prone to failure after more than 20 years of use. From 1975 onward they used the K-Jetronic mechanical fuel injection system, a less complicated system that proved to be much more reliable in the long run with injectors costing significantly less than those used on the D-Jetronic system. The W116 equipped with the K-Jetronic system used a cast-iron fuel distributor which can be prone to rust over time if moisture or water is present in the fuel. This was changed to an alloy fuel distributor in the following model W126 and is not subject to corrosion.
| Chassis code | Model Years | Model | Engine | No. built |
| W116.020 | 1973–1980 | 280 S | 2.8 L M110 I6 | 122,848 |
| W116.024 | 1973–1980 | 280 SE | 2.8 L M110 I6 | 150,593 |
| W116.025 | 1974–1980 | 280 SEL | 2.8 L M110 I6 | 7,032 |
| W116.028 | 1973–1980 | 350 SE | 3.5 L M116 V8 | 51,100 |
| W116.029 | 1973–1980 | 350 SEL | 3.5 L M116 V8 | 4,266 |
| W116.032 | 1973–1980 | 450 SE | 4.5 L M117 V8 | 41,604 |
| W116.033 | 1973–1980 | 450 SEL | 4.5 L M117 V8 | 59,578 |
| W116.036 | 1975–1980 | 450 SEL 6.9 | 6.8 L M100 V8 | 7,380 |
| W116.120 | 1978–1980 | 300SD | 3.0 L OM617 turbodiesel I5 (United States and Canada only) | 28,634 |

## Hydropneumatic suspension

W116 was first model from Mercedes-Benz to feature the hydropneumatic suspension system. While the principle is similar to Citroën’s, Mercedes-Benz made some changes. The hydraulic pump was driven by the timing chain instead of a rubber belt for more reliability (Citroën’s system would lead to loss of hydraulic power if belt failed). Mercedes-Benz utilised the hard rubber dampers as temporary dampers in event of hydraulic failure. The height adjustment had a smaller range of height as compared to Citroën (5 cm versus 50 cm). Unlike Citroën, the car did not “sink” to the ground after shutting off the engine, and the driver did not have to wait for the hydraulic power to spool up and lift the car to the operating height.
The full hydropneumatic suspension system was fitted to the 450SEL 6.9 as standard. In 1977, the self-levelling rear suspension system was offered for 450SEL as an extra cost option outside the North American market.

## North American sales

North America was a key market for the W116. The model range for the U.S. market at for MY 1973 was 450SE and 450SEL. Initially both models were unique to the US market, carrying on the tradition of the 4.5 litre W108/109 versions they replaced (and would become available in Europe only in early 1973). For MY 1975, the 280S was launched as a response to the 1973 oil crisis. For MY 1977 model year the 280S and 450SE were dropped due to slow sales and replaced with the 280SE. The 6.9 was added for 1978 and 1979 model years with the MSRP of $38,230.
Due to the modifications demanded by the U.S. government, American Mercedes-Benz W116 were described by journalists as if a "beautiful car was beaten with the malaise ugly stick." Furthermore the US models performance was being continuously hampered by the ever stringent emission control and fuel economy legislation. Upon launch the M117 engine for the US market developed a SAE net rating of 192 hp at 4750 RPM and 325 Nm at 3000 RPM for a car with curb weight of 1743 kg (450SEL - 1755kg). In the final 1980 model year, the 450SEL was making 162 hp at 4200 RPM and 312 Nm at 2500, weighing 1810 kg. For comparison, the European 450SEL weighed 1765 kg, and its M117 made 225 hp at 5000 RPM at start and finish and 368 Nm at 3250 RPM at finish (performance would be adjusted twice - in November 1975 during the switch to K-Jetronic and it's re-calibration in April 1978).
The 300SD, the world’s first passenger car with a turbocharged diesel engine, was launched in the United States and Canada in 1978. The S-Class model with the turbodiesel engine was exclusive to the North American and Japanese markets until 1991. It had a turbocharged 3.0-litre inline-five diesel engine developed from the C111 experimental vehicle, developed to help Mercedes-Benz keep from falling afoul of US Corporate Average Fuel Economy (CAFE) standards introduced in 1975. The 300D became a best seller and helped considerably raise Mercedes-Benz's average fuel economy.

## 450SEL 6.9

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

## Technical data

Technical data Mercedes-Benz W116 (Manufacturer's figures except where stated) :
| Model | 280 S | 280 SE 280 SEL | 350 SE 350 SEL | 450 SE 450 SEL | 450 SEL 6.9 | 300 SD |
| Type: | W 116 V28 | W 116 E28 | W 116 E35 | W 116 E45 | W 116 E69 | W 116 D30A |
| Chassis code: | 116.020 | 116.024 116.025 | 116.028 116.029 | 116.032 116.033 | 116.036 | 116.120 |
| Produced: | 1972–1980 | 1972–1980 1974−1980 | 1972–1980 1973−1980 | 1972–1980 | 1975–1980 | 1978–1980 |
| Engine: | 6-cylinder-inline engine (four-stroke), front-mounted | 6-cylinder-inline engine (four-stroke), front-mounted | 90° 8-cylinder-V engine (four-stroke), front-mounted | 90° 8-cylinder-V engine (four-stroke), front-mounted | 90° 8-cylinder-V engine (four-stroke), front-mounted | 5-cylinder-inline engine (four-stroke), front-mounted |
| Bore x Stroke: | 86 mm x 78.8 mm | 86 mm x 78.8 mm | 92 mm x 65.8 mm | 92 mm x 85 mm | 107 mm x 95 mm | 90.9 mm x 92.4 mm |
| Displacement: | 2746 cc | 2746 cc | 3499 cc | 4520 cc | 6834 cc | 2998 cc |
| Engine code: | M110.922 | D-Jet: M110.983 K-Jet: M110.985 | D-Jet: M116.983 K-Jet: M116.985 | D-Jet: M117.983 K-Jet: M117.986 | M100.985 | OM617.950 |
| Max. Power at rpm: | 160 PS (118 kW; 158 hp) at 5,500 USA: 120 hp (89 kW; 122 PS) at 4,800 | 185 PS (136 kW; 182 hp) at 6,000 USA: 142 hp (106 kW; 144 PS) at 5,750 | 200 PS (147 kW; 197 hp) at 5,800 | 225 PS (165 kW; 222 hp) at 5,000 USA: 190 hp (142 kW; 193 PS) at 4,750 | 286 PS (210 kW; 282 hp) at 4,250 USA: 250 hp (186 kW; 253 PS) at 4,000 | 1979: 110 hp (82 kW; 112 PS) at 4,200 1980: 120 hp (89 kW; 122 PS) at 4,350 |
| Max. Torque at rpm: | 225 N⋅m (166 lb⋅ft) at 4,000 USA: 143 lb⋅ft (194 N⋅m) | 238 N⋅m (176 lb⋅ft) at 4,500 USA: 149 lb⋅ft (202 N⋅m) | 286 N⋅m (211 lb⋅ft) at 4,000 | 377 N⋅m (278 lb⋅ft) at 3,000 USA: 240 lb⋅ft (325 N⋅m) | 550 N⋅m (406 lb⋅ft) at 3,000 USA: 360 lb⋅ft (488 N⋅m) | 1979: 168 lb⋅ft (228 N⋅m) at 2,400 1980: 170 lb⋅ft (230 N⋅m) at 2,400 |
| Compression Ratio: | 9.0: 1 | 9.0: 1 | 9.5: 1 | 8.8: 1 | 8.8: 1 | 21.5: 1 |
| Fuel feed: | One 2-bbl Solex 4A1 | Bosch D-Jetronic, from July 1975 K-Jetronic | Bosch D-Jetronic, from July 1975 K-Jetronic | Bosch D-Jetronic, from July 1975 K-Jetronic | Bosch K-Jetronic | Bosch injection pump Garrett turbine |
| Fuel tank capacity: | 96 L (25.4 US gal; 21.1 imp gal) | 96 L (25.4 US gal; 21.1 imp gal) | 96 L (25.4 US gal; 21.1 imp gal) | 96 L (25.4 US gal; 21.1 imp gal) | 96 L (25.4 US gal; 21.1 imp gal) | 82 L (21.7 US gal; 18.0 imp gal) |
| Valvetrain: | DOHC, duplex chain | DOHC, duplex chain | SOHC, duplex chain | SOHC, duplex chain | SOHC, duplex chain | SOHC, duplex chain |
| Cooling: | Water | Water | Water | Water | Water | Water |
| Gearbox: | 4-speed or 5-speed manual or 4-speed automatic rear wheel drive, standard axle ratio 3.69:1 or 3.92:1 (5-speed) | 4-speed or 5-speed manual or 4-speed automatic rear wheel drive, standard axle ratio 3.69:1 or 3.92:1 (5-speed) | 4-speed manual or 3-speed automatic rear wheel drive standard axle ratio 3.46:1 | 3-speed automatic rear wheel drive standard axle ratio 3.07:1 | 3-speed automatic rear wheel drive standard axle ratio 2.65:1 | 4-speed automatic rear wheel drive standard axle ratio 3.07:1 |
| Automatic gearbox: model (type) | W4B 025 (722.1) | W4B 025 (722.1) | W3A 040 (722.0) | W3B 050 (722.0) Worldwide W3A 040 (722.0) USA & Japan | W3B 050 reinf. (722.003) | W4B 025 (722.1) |
| Electrical system: | 12 volt | 12 volt | 12 volt | 12 volt | 12 volt | 12 volt |
| Front suspension: | Double wishbones, coil and additional rubber springs, stabilising bar 6.9: Double wishbones, hydropneumatic damping, stabilizing torsion bar | Double wishbones, coil and additional rubber springs, stabilising bar 6.9: Double wishbones, hydropneumatic damping, stabilizing torsion bar | Double wishbones, coil and additional rubber springs, stabilising bar 6.9: Double wishbones, hydropneumatic damping, stabilizing torsion bar | Double wishbones, coil and additional rubber springs, stabilising bar 6.9: Double wishbones, hydropneumatic damping, stabilizing torsion bar | Double wishbones, coil and additional rubber springs, stabilising bar 6.9: Double wishbones, hydropneumatic damping, stabilizing torsion bar | Double wishbones, coil and additional rubber springs, stabilising bar 6.9: Double wishbones, hydropneumatic damping, stabilizing torsion bar |
| Rear suspension: | Diagonal swing axle, trailing arms, coil springs, stabilizing torsion bar 6.9: Diagonal swing axle, hydropneumatic damping, stabilizing torsion bar · 4.5 and 6.9: anti-squat-device | Diagonal swing axle, trailing arms, coil springs, stabilizing torsion bar 6.9: Diagonal swing axle, hydropneumatic damping, stabilizing torsion bar · 4.5 and 6.9: anti-squat-device | Diagonal swing axle, trailing arms, coil springs, stabilizing torsion bar 6.9: Diagonal swing axle, hydropneumatic damping, stabilizing torsion bar · 4.5 and 6.9: anti-squat-device | Diagonal swing axle, trailing arms, coil springs, stabilizing torsion bar 6.9: Diagonal swing axle, hydropneumatic damping, stabilizing torsion bar · 4.5 and 6.9: anti-squat-device | Diagonal swing axle, trailing arms, coil springs, stabilizing torsion bar 6.9: Diagonal swing axle, hydropneumatic damping, stabilizing torsion bar · 4.5 and 6.9: anti-squat-device | Diagonal swing axle, trailing arms, coil springs, stabilizing torsion bar 6.9: Diagonal swing axle, hydropneumatic damping, stabilizing torsion bar · 4.5 and 6.9: anti-squat-device |
| Brakes: | Disc brakes (Ø 278 mm front, 279 mm rear), power assisted, from 1979 on request ABS | Disc brakes (Ø 278 mm front, 279 mm rear), power assisted, from 1979 on request ABS | Disc brakes (Ø 278 mm front, 279 mm rear), power assisted, from 1979 on request ABS | Disc brakes (Ø 278 mm front, 279 mm rear), power assisted, from 1979 on request ABS | Disc brakes (Ø 278 mm front, 279 mm rear), power assisted, from 1979 on request ABS | Disc brakes (Ø 278 mm front, 279 mm rear), power assisted, from 1979 on request ABS |
| Steering: | Recirculating ball steering, manual or servo-assisted | Recirculating ball steering, manual or servo-assisted | Recirculating ball steering, manual or servo-assisted | Recirculating ball steering, manual or servo-assisted | Recirculating ball steering, manual or servo-assisted | Recirculating ball steering, manual or servo-assisted |
| Body structure: | Sheet steel, monocoque (unibody) construction | Sheet steel, monocoque (unibody) construction | Sheet steel, monocoque (unibody) construction | Sheet steel, monocoque (unibody) construction | Sheet steel, monocoque (unibody) construction | Sheet steel, monocoque (unibody) construction |
| Curb weight: | 1,660 kg (3,660 lb) USA: 3,770 lb (1,710 kg) | 1,665 kg (3,671 lb) 1,700 kg (3,748 lb) USA: 3,750 lb (1,701 kg) | 1,725 kg (3,803 lb) 1,760 kg (3,880 lb) | 1,740 kg (3,836 lb) 1,825 kg (4,023 lb) USA: 3,843 lb (1,743 kg) | 1,985 kg (4,376 lb) USA: 4,285 lb (1,944 kg) | 1,815 kg (4,001 lb) |
| Loaded weight: | 2,130 kg (4,696 lb) | 2,130 kg (4,696 lb) 2,165 kg (4,773 lb) | 2,195 kg (4,839 lb) 2,220 kg (4,894 lb) | 2,250 kg (4,960 lb) 2,285 kg (5,038 lb) | 2,420 kg (5,335 lb) | 2,215 kg (4,883 lb) |
| Track front · rear: | 1,521 mm (59.9 in) · 1,505 mm (59.3 in) | 1,521 mm (59.9 in) · 1,505 mm (59.3 in) | 1,521 mm (59.9 in) · 1,505 mm (59.3 in) | 1,521 mm (59.9 in) · 1,505 mm (59.3 in) | 1,521 mm (59.9 in) · 1,505 mm (59.3 in) | 1,521 mm (59.9 in) · 1,505 mm (59.3 in) |
| Wheelbase: | 2,865 mm (112.8 in) 2,965 mm (116.7 in) | 2,865 mm (112.8 in) 2,965 mm (116.7 in) | 2,865 mm (112.8 in) 2,965 mm (116.7 in) | 2,860 mm (112.6 in) 2,960 mm (116.5 in) | 2,860 mm (112.6 in) 2,960 mm (116.5 in) | 2,865 mm (112.8 in) |
| Length: | 4,960 mm (195.3 in) 5,060 mm (199.2 in) | 4,960 mm (195.3 in) 5,060 mm (199.2 in) | 4,960 mm (195.3 in) 5,060 mm (199.2 in) | 4,960 mm (195.3 in) 5,060 mm (199.2 in) | 4,960 mm (195.3 in) 5,060 mm (199.2 in) | 4,960 mm (195.3 in) 5,060 mm (199.2 in) |
| Width: | 1,870 mm (73.6 in) | 1,870 mm (73.6 in) | 1,870 mm (73.6 in) | 1,870 mm (73.6 in) | 1,870 mm (73.6 in) | 1,870 mm (73.6 in) |
| Height: | 1,410 mm (55.5 in) 1,430 mm (56.3 in) | 1,410 mm (55.5 in) 1,430 mm (56.3 in) | 1,410 mm (55.5 in) 1,430 mm (56.3 in) | 1,410 mm (55.5 in) 1,430 mm (56.3 in) | 1,410 mm (55.5 in) 1,430 mm (56.3 in) | 1,410 mm (55.5 in) 1,430 mm (56.3 in) |
| Tyre/Tire sizes: | 185 HR 14 | 185 HR 14 | 205/70 VR 14 | 205/70 VR 14 | 215/70 VR 14 | 185 HR 14 |
| Acceleration 0–100 km/h (0-62 mph): | 11.5 s | 10.5 s | 9.5 s (SEL 10.0 s) | 8.5 s (SEL 8.9 s) | 7.4 s | 17.0 s 16.2 s (from 10.1979) |
| Top speed: | 190 km/h (118 mph) | 200 km/h (124 mph) | 205 km/h (127 mph) | 210 km/h (130 mph) | 225 km/h (140 mph) | 165 km/h (103 mph) |
| Fuel Consumption (guideline DIN 70030: determined at 3/4 of top-speed (not more than 110 km/h), plus 10%): | 12.5 L/100 km (18.8 mpg$_{‑US}$; 22.6 mpg$_{‑imp}$) | 12.5 L/100 km (18.8 mpg$_{‑US}$; 22.6 mpg$_{‑imp}$) | 13.0 L/100 km (18.1 mpg$_{‑US}$; 21.7 mpg$_{‑imp}$) | 14.5 L/100 km (16.2 mpg$_{‑US}$; 19.5 mpg$_{‑imp}$) | 16.0 L/100 km (14.7 mpg$_{‑US}$; 17.7 mpg$_{‑imp}$) | 10.6 L/100 km (22 mpg$_{‑US}$; 27 mpg$_{‑imp}$) |

## Features

The W116 S-Class incorporated a broad variety of Mercedes-Benz safety innovations.
* Four wheel anti-lock brakes were first featured as an option on the 1978 W116 S-Class. This system prevents the wheels from locking while braking. The system improves steering control during hard braking situations, and to shorten brake distances.
* Strengthened body structure. The W116 featured a more stable security passenger cell with a stiffened roof frame structure. High strength roof and door pillars, along with other reinforced zones, provided enhanced vehicle occupant protection.
* Deformation zones (crumple zones) in the front and rear.
* A padded dashboard, deformable switches and controls, and a four-spoke steering wheel with impact absorber and broad impact cushion aimed to reduce occupant injury during collisions.
* The fuel tank was no longer fitted at the rear end, but was now placed above the rear axle for added protection.
* Wraparound turn signals made it easier to communicate with nearby drivers.