Mercedes-Benz · 1979–present

Mercedes-Benz W126

The Mercedes-Benz W126 is a series of passenger cars made by Daimler-Benz AG. It was marketed as the second generation of the Mercedes-Benz S-Class, and manufactured in sedan/saloon (1979–1991) as well as coupé (1981–1990) models, succeeding the company's W116 range. Mercedes-Benz introduced the 2-door C126 coupé model, marketed as the SEC, in September 1981. This generation was the first S-Class to have separate chassis codes for standard and long wheelbases (W126 and V126) and for coupé (C126). Over its 12-year production (1979–1991), 818,072 sedans/saloons and 74,060 coupés were manufactured, totaling 892,126 and making the W126 by far the most successful generation of S-Class to date, and the longest in production.

Text from Wikipedia (CC BY-SA 4.0).

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History

After the debut of the W116 S-Class in 1972, Mercedes-Benz began preparing for the next generation S-Class, in October 1973. The project, code-named "Project W126", aimed to provide an improved ride, better handling, and improved fuel efficiency. The 1973 oil crisis and increasingly stringent emission and safety regulations in the United States influenced the development of the W126, leading to reduced emissions and improved fuel efficiency. The W126 design team, led by Mercedes-Benz's chief designer Bruno Sacco, aimed to design a more aerodynamic shape and retain the unmistakable S-Class design elements. The aerodynamic drag was reduced through lengthy wind tunnel testing and reshaping of the front end and bumper along with hiding the wipers underneath the hood/bonnet for smoother flow. Reducing the weight was accomplished by extensive use of high-strength low-alloy (HSLA) sheet and polyurethane deformable material for bumpers and side claddings. The lighter alloy material was used for the heavily revised M116/M117 V8 engines for reduced weight. Both contributed to the reduction of fuel consumption by 10% as compared to its predecessor. After six years of development, the W126 was introduced at the IAA Frankfurt in September 1979. At the introduction, S-Class was available in two wheelbase lengths (standard and long) and three petrol engine options with one six-cylinder inline engine and two V8 engines. The diesel engine option was introduced in September 1981 exclusively for the North American market. At the 1981 IAA Frankfurt, the C126, a coupé version of the S-Class, was introduced with 380 SEC and 500 SEC trims initially offered. It was the first time that a coupé version was derived from an S-Class chassis. However, the styling was different between the two, makin

Styling

From 1973 to 1975, Mercedes-Benz designers worked on the successor to the W116. After several design concepts were presented, the final design for the W126 was approved and frozen in 1976. The design work for the coupé began immediately after the approval and was finalised in 1977. Design patents were first filed on 3 March 1977 and later on 6 September 1977 at the United States Patent Office. Compared to its predecessor, the W116, the W126 featured improved aerodynamics with a drag coefficient of Cd 0.36 for the sedan/saloon and 0.34 for the coupés.

Models

The pre-facelift model range (1979–1985 for sedan/saloon and 1982–1985 for coupé) included the 280 S/SE/SEL, 300 SD (North American market only), 380 SE/SEL/SEC, and 500 SE/SEL/SEC. The revised second series (1986–1991) with petrol engines included 260 SE, 300 SE/SEL, 420 SE/SEL/SEC, 500 SE/SEL/SEC, and 560 SE/SEL/SEC. The updated version of the diesel model, 300 SDL, was exclusive to the North American market (the first time the S-Class with diesel engine was offered in long wheelbase) and then the 350 SD/SDL (the first diesel S-Class to be available in both wheelbase lengths). Safety. Use of high-strength low-alloy (HSLA) sheet in its construction to reduce the weight without compromising the structural strength and integrity. Anti-lock braking system (ABS) (first appeared in its predecessor, the W116). It was an optional extra for all models and engines until late December of 1984 when it was made standard for the V8 models. Anti-lock braking system (ABS) became standard equipment in September of 1986 for the 260 SE, 300 SE and 300 SEL. Anti-lock braking system (ABS) was standard in the U.S spec 300 SDL, 350 SD and 350 SDL. Seat Belt Pretensioners enabled all seat belts (with exception of rear centre shoulder belt on sedan/saloon) to tighten when the car sensed conditions that could lead to an accident such as sudden, forceful braking or sudden deceleration during the collision. Crumple zones front and rear which absorbed impact energies, reducing passenger injury. Fluted taillamps, the design pioneered on the R107/C107, was carried over. The fluted design maintains the visibility of taillamps when the dirt accumulates on the outer edges. Airbags The driver's side airbag was introduced in 1981 as an extra-cost option for all models and engines. The consumers could ei

Engines

=== First series (1979–1985) === At the introduction in September 1979, the 2.7-litre DOHC six-cylinder inline M110 engine from the 280 S/SE/SEL was carried over from the W116. The revised M116/M117 V8 engines had a significant innovation: an aluminium block without iron sleeves, as found in the competitors' engines. Mercedes-Benz developed a special silicon coating as to harden the cylinder liners against excessive wear and tear. The V8 engines were offered in two sizes: 3.8 litres (M116) and 5 litres (M117). The M116 V8 engine had a single timing chain, while the M117 V8 engine had double timing chains. The frequent mechanical failure of the single timing chain in the M116 was addressed in 1982 by switching to double timing chains from the M117 V8 engine. The smaller of the two V8 engines was initially the only one offered in the US market, to help meet Corporate Average Fuel Economy (CAFE) requirements. The 380 SEL received a poor customer perception in the United States as being severely underpowered and due to mechanical issues with the single timing chain. The 380 SEL for the US market took 11 seconds to reach 60 mph (97 km/h) from standstill and had top speed of 117 mph (188 km/h). The severe performance shortcoming of W126 with V8 engine was addressed by introducing more powerful 500SEL/SEC in 1984. The S-Class coupé was fitted with V8 engines only for the first time.The 3-litre five-cylinder inline OM617 diesel engine was carried over from the W116 with the same performance. The diesel engines were again never offered in the markets outside of the United States and Canada. This discrepancy was not addressed until 1994 when the W140 S 350 Turbodiesel was introduced in Europe. In 1981, Mercedes-Benz introduced the Energiekonzept ("Energy Concept") programme in

Transmissions

=== First series (1979–1985) === The automatic transmission 4G-Tronic had four speeds with direct drive in the fourth gear for the entire run from 1979 to 1991. The 280 S/SE/SEL had 4-speed manual transmission as standard with 5-speed manual and 4-speed automatic transmissions as extra-cost options. Manual transmission was not fitted to the V8 engines. U.S. models, including the 300 SD Turbodiesel, had automatic transmission as sole transmission choice. Second series (1985–1991). From 1986 onward, the automatic transmission 4G-Tronic was revised to include the option of selecting S (Standard) and E (Economy) shifting points. The models 260 SE and 300 SE/SEL were fitted with the standard 5-speed manual and optional extra-cost 4-speed automatic transmissions. For one year from September 1986 to June 1987, the extra cost automatic transmission option wasn't offered for the 260 SE and 300 SE. Manual transmission was not fitted to the V8 engines. U.S. models had the automatic transmission as the sole transmission choice.

U.S. grey market

When the W126 was introduced in the United States in September 1980, Mercedes-Benz only offered the smaller 3.8-litre V8 engine to avoid the gas guzzler penalty under Corporate Average Fuel Economy (CAFE) regulations. However, American consumers found the 380 SEL severely underpowered with slow acceleration (0–60 mph in 11 seconds) and a lower top speed of 117 mph (188 km/h). As the fear of oil crisis waned in 1982, American consumers demanded the more powerful S-Class models, and grey importers brought the S-Class with 5-litre V8 engines to the United States and modified them to meet US FMVSS and EPA regulations. The 280 S/SE/SEL with smaller six-cylinder inline engines were also imported, offering significant savings over the V8 models. The W126 was a major part of this parallel market, with 22,000 imported in a segment that hit 66,900 cars in 1985, the biggest year for grey imports. Consequently, Mercedes-Benz added the 500 SEL/500 SEC to the American model range for 1984 model year to counter the grey imports while the 3.8-litre V8 engine remained in 380 SE (standard wheelbase only) and 380 SL. In 1988, an intense lobbying effort by Mercedes-Benz and other foreign manufacturers led U.S. Congress to eliminate this consumer option and revise the rules for registered importers.

Sections adapted from Wikipedia (CC BY-SA 4.0); text is shortened. Read the full article for the complete history and citations.

Specifications

name: Mercedes-Benz W126/C126
Manufacturer: Daimler-Benz
Production: December 1979 – October 1991 (sedan), September 1981 – October 1991 (coupé), 1980–1993 (sedan, South Africa), 1982–1991 (coupé, South Africa)
Model years: 1981–1991 (North America)
Assembly: Germany: Sindelfingen, Malaysia: Johor Bahru (OASB), South Africa: East London
Predecessor: Mercedes-Benz W116 (sedan), Mercedes-Benz C107 (coupé)
Successor: Mercedes-Benz W140, Mercedes-Benz C140 (coupé)
Related: Monteverdi Tiara
Layout: FR layout
Class: Full-size luxury car (F), Grand tourer (C126)
Body style: 4-door sedan, 2-door coupé (C126)
Transmission: 4-speed 4G-TRONIC automatic, 4-speed manual, 5-speed manual
Engine: petrol, 2.6 L M103 I6, 2.7 L M110 I6, 3.0 L M103 I6, 3.8 L M116 V8, 4.2 L M116 V8, 5.0 L M117 V8, 5.5 L M117 V8, diesel:, 3.0 L OM617 I5, 3.0 L OM603 I6, 3.5 L OM603 I6
Designer: Bruno Sacco, Werner Breitschwerdt (sedan: 1975, 1976; coupe: 1977)
Wheelbase: SWB Sedan: 2935 mm, LWB Sedan: 3075 mm, Coupe: 2850 mm
Length: SWB Sedan: 4995 -, LWB Sedan: 5135 -, Coupe: 4910 -
Width: Sedan: 1820 mm, Coupe: 1828 mm
Height: SWB Sedan: 1430 -, LWB Sedan: 1441 mm, Coupe: 1406 mm