Mercedes-Benz W126

Mercedes-Benz W126
Overview
Manufacturer	Mercedes-Benz (Daimler-Benz)
Production	December 1979 – April 1993 (sedan) September 1981 – October 1991 (coupé)
Assembly	Germany: Sindelfingen South Africa: East London
Designer	Bruno Sacco (1975, 1976)
Body and chassis
Class	Full-size luxury car Grand tourer
Body style	2-door coupé 4-door sedan
Layout	FR layout
Powertrain
Engine	Straight-5 3.0 L OM617 diesel Straight-6 2.6 L M103 2.8 L M110 3.0 L M103 3.0 L OM603 diesel 3.5 L OM603 diesel V8 3.8 L M116 4.2 L M116 5.0 L M117 5.6 L M117
Transmission	4-speed automatic 4-speed manual 5-speed manual
Dimensions
Wheelbase	Sedan (SWB): 115.6 in (2,936 mm) Sedan (LWB): 120.9 in (3,071 mm) Coupe: 112.2 in (2,850 mm)
Length	Sedan (SWB): 197.6 in (5,019 mm) Sedan (LWB): 203.1 in (5,159 mm) Coupe: 193.3 in (4,910 mm)
Width	Sedan: 71.7 in (1,821 mm) Coupe: 72.0 in (1,829 mm)
Height	Sedan: 56.7 in (1,440 mm) Coupe: 55.0 in (1,397 mm)
Chronology
Predecessor	Mercedes-Benz W116 (sedan) Mercedes-Benz C107 (coupé)
Successor	Mercedes-Benz W140

The Mercedes-Benz W126 is a series of flagship vehicles manufactured by German automotive marque Mercedes-Benz. Premiering in September 1979 as the successor to the earlier W116 line, the W126 was the second generation of the Mercedes-Benz flagship to officially bear the S-Class name referring to Sonderklasse or "special class." The W126 was initially offered in straight-6, V8, and turbo diesel sedan models. In September 1981, 2-door coupé versions of the W126 were introduced. Compared to its predecessor, the W126 was more aerodynamic, fuel efficient, capacious, and powerful. The W126 S-Class debuted a new Mercedes-Benz design style which was subsequently used on other vehicles in the company's lineup. The W126 line also introduced many Mercedes-Benz safety innovations, including the first seatbelt pretensioners.^[1]

The W126 had a twelve-year production run between 1979 and 1991, the longest of any S-Class generation since the flagship models were first built in the mid-1950s.^[1][2]

History

Following the debut of the 1970s generation W116 (which also included the flagship Mercedes-Benz 450SEL 6.9), Mercedes-Benz began plans for the next-generation S-Class model in October 1973. Codenamed "project W126,"^[1] the project had specific goals: an improved ride, better handling, and improved fuel efficiency.^[2] These improvements were aimed at helping retain the S-Class' market leadership as the world's best-selling prestige luxury sedan.^[1] Following the 1970s oil crisis, Mercedes-Benz had made fuel efficiency an especially pertinent goal (named "Energy Program"),^[3] even in the large V8 engined versions of the S-Class.

In terms of the body design, the objective of the W126 design team, led by Mercedes-Benz's Bruno Sacco, was to produce a car that was sleeker and more aerodynamic than the previous model. The application of lighter materials and alloys combined with thorough wind tunnel testing to reduce overall drag meant the car consumed about 10% less fuel than its predecessor.^[2] The maximum speed was also increased (250 km/h in the most powerful model).^[1]

After six years of development, the W126 was formally introduced at the Internationale Automobil-Ausstellung (International Motor Show, or IAA) in Frankfurt on September 1979. The initial lineup featured seven models in standard (SE, SD) and long (SEL, SDL) wheelbase sedan body styles: the 280 SE/SEL, 380 SE/SEL, 500 SE/SEL and 300 SD. Technically, the long-wheelbase (SEL) variants were codenamed V126, but this was not popularly known.^[1] In 1981, the coupé version (SEC) of the W126 S-Class premiered at the IAA with the 500 SEC model. In 1981, Wheels Magazine selected the W126 model 380 SE as its Car of the Year.^[4]

Four years after the introduction of the fuel-efficiency "Energy Program," the model range had been reworked completely. In September 1985, again at the IAA in Frankfurt, the reworked model range was reintroduced. Apart from visual changes to the bumpers, side covers and alloys, the changes made to the available collection of engine variants was most visible. Two newly constructed 6-cylinder engines and new 4.2 and 5.6 litre V8's were added, and other engines were further upgraded.

The W126 generation was replaced by the W140 in 1991, although a satellite factory in South Africa is known to have continued production until 1994. The different body styles of the W126 S-Class achieved a combined sales total of 892,123 units (818,063 sedans and 74,060 coupés), making the W126 the most popular S-Class ever produced.

Styling

From 1973 to 1975, Mercedes-Benz designers worked on the successor to the W116. In December 1975, after several design concepts being presented, the design for the W126 S-Class was approved and frozen in 1976.^[5] Design work on the coupe began immediately afterward, being finalized in 1977. It premiered the next generation of Mercedes-Benz car styling, which came to dominate the lineup in the 1980s. Compared to its predecessor, the W116, the new model had more aerodynamic qualities than before, with a (drag coefficient of Cd 0.36 for the sedans, 0.34 for the coupés).^[1] For the first time, a Mercedes-Benz sedan was not equipped with traditional chrome bumpers; polyurethane deformable bumpers were used, and visually aligned with body panels.^[2] Design patents were first filed on March 3, 1977 and later on September 6, 1977 at the United States Patent Office.^[6]

The interior featured pleated leather on the doors on later cars and woodgrain trim on the center console and across the dash, and a simplified layout with symmetrically placed buttons. Both zebrano and burled walnut were used on low/mid and high-end cars, respectively.

Models

The W126 series (named in accordance to their engine size) initially included the 280, 300, 380, and 500 series models. Following the first S-Class mid-cycle refresh, the W126 series included 260, 300, 350, 420, 500, and 560 models. Variants included SE (standard wheelbase), SEL (long-wheelbase), SEC (coupé), and diesel models (SD / SDL).

Years	Model	Chassis	Engine	Market	Built
1979–1985	280 S	W126.021	M110.924 2.8L I6 carburetor	N/A in US	42,996
1979–1985	280 SE	W126.022	M110.987 2.8L I6	N/A in US	133,955
1979–1985	380 SE	W126.032	M116.963 3.8L V8		58,239
1979–1985	500 SE	W126.036	M117.963 5.0L V8	N/A in US & AU	33,418 (79–91)
1980–1985	280 SEL	W126.023	M110.987 2.8L I6	N/A in US	20,655
1980–1985	300 SD	W126.120	OM617.951 3.0L I5	US & CA only	78,725
1980–1985	380 SEL	W126.033	M116.963 3.8L V8		27,014
1980–1985	500 SEL	W126.037	M117.963 5.0L V8		72,733 (80–91)
1980–1985	500 SEC	W126.044	M117.963 5.0L V8		30,184 (80–91)
1981–1985	380 SEC	W126.043	M116.963 3.8L V8		11,267
1985–1991	260 SE	W126.020	M103.941 2.6L I6	N/A in US & AU	20,836
1985–1991	300 SE	W126.024	M103.981 3.0L I6		105,422
1985–1991	420 SE	W126.034	M116.965 4.2L V8	N/A in US	13,996
1985–1991	420 SEL	W126.035	M116.965 4.2L V8		74,017
1985–1991	420 SEC	W126.046	M116.965 4.2L V8	N/A in US	3,680
1985–1991	500 SE	W126.036	M117.965 5.0L V8	N/A in US
1985–1991	500 SEL	W126.037	M117.965 5.0L V8	N/A in US
1985–1991	500 SEC	W126.044	M117.965 5.0L V8	N/A in US
1985–1991	560 SEL	W126.039	M117.968 5.5L V8		75,071
1985–1991	560 SEC	W126.045	M117.968 5.5L V8		28,929
1985–1993	300 SEL	W126.025	M103.981 3.0L I6		40,956
1986–1987	300 SDL	W126.125	OM603.961 3.0L I6	US & CA Only	13,830
1988–1991	560 SE	W126.038	M117.968 5.5L V8	N/A in US & AU	1,251
1991	350 SD	W126.134	OM603.97 3.5L I6	US & CA Only	2,066
1990–1991	350 SDL	W126.135	OM603.97 3.5L I6	US & CA Only	2,925
Saloon Total[7]					818,105
Coupe Total[7]					74,060

Dimensions and weight

Body style	Wheelbase	Length	Width	Height	Curb weight
Sedan (short-wheelbase)	2,935 mm (115.6 in)	5,020 mm (197.6 in)	1,820 mm (71.7 in)	1,437 mm (56.6 in)	1,640 kg (3,616 lb)
Sedan (long-wheelbase)	3,070 mm (120.9 in)	5,160 mm (203.1 in)	1,820 mm (71.7 in)	1,441 mm (56.7 in)	1,670 kg (3,682 lb)
Coupe	2,850 mm (112.2 in)	4,910 mm (193.3 in)	1,828 mm (72.0 in)	1,406 mm (55.4 in)	1,610 kg (3,549 lb)
[8][9][10]

Timeline

v t e Mercedes-Benz W126 timeline
Type	1970s										1980s										1990s
	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4	5	6	7	8	9
280 S
280 SE
380 SE
500 SE
280 SEL
300 SD
380 SEL
500 SEL
500 SEC
380 SEC
260 SE
300 SE
420 SE
420 SEL
420 SEC
560 SEL
560 SEC
300 SEL
300 SDL
560 SE
350 SD
350 SDL

Features

Novel luxury features/options included the following safety, comfort, and technological features. Whilst almost all of these features are available on modern luxury cars today, each in its own right was considered very significant in the 1980s. The harmonious and "matter-of-fact" way which these were combined, as well as their renowned durability, has added to the appeal of W126.

Safety

• Airbags, as an additional measure of occupant protection. The driver side airbag premiered on 1981 models, as an optional extra (standard from 1985 on 500 SEL and 500 SEC), and the passenger side airbag premiered in 1987 and became available in February 1988 (as an optional extra; due to its expense, few early production W126 cars were thus equipped). The passenger side airbag became standard in 1989 for the U.S. V8 models and was made standard in 1990 for all 1991 models.^[2]

• Traction control system (TCS), also known as Acceleration Slip Regulation (ASR) to prevent wheelspin (a Mercedes-Benz first). Available only on European models from 1989 until the model year 1991, when it was introduced on 560 SEL and SEC models in the United States for that last production year only.

• Seat belt pretensioners ETR enabled all seat belts (with exception of rear centre lap belt on sedans) to tighten when the car sensed conditions that could lead to an accident (such as sudden, forceful braking).

• Anti-lock braking system (ABS) (as introduced by its predecessor, the W116) was optional until 1986 except on premier 500 SEL and 500 SEC models.
• Crumple zones which absorbed impact energies, reducing passenger injury.

• Fluted taillights continuing the design pioneered on the W116, a design that helped maximise visibility of taillights from behind the car even when extremely dirty

• A third brakelight from 1986 on US-model cars, which provided a third brake lamp in the center of the rear windscreen as a safety feature. This change was mandated by US law for all foreign and domestic US-model cars as of the 1986 model year.

Comfort and convenience

• Courtesy lights on the underside of the doors, to enable the occupant to see the ground when exiting the vehicle in the dark. And on sedan models, individual, rear cabin reading lamps aimed at the rear-seat occupants' laps so as to avoid distracting the driver at night.

• Eight-way powered, dual stage heated front seats, with two setting memory functions for both front occupants to retain positions of power adjustable steering column and seat position for driver; and seat position for front passenger. The seat heaters were standard on the 560 SEL/SEC, and an option on other models. Later-production (post-facelift) models so equipped had higher wattage heated seats, as compared to earlier models.

• Two-way powered, dual stage heated rear "Chesterfield" bench seat (pre-1990 SELs) with four-way manually adjustable rear headrests that was standard on flagship 500 SEL and 560 SEL models.

• As an option on the 500 SEL and 560 SEL, individual, power adjustable rear seats were provided with a burl walnut grained centre console that replaced the centre seat to allow for a 2 + 2 seating format.

• An optional fully automatic climate control system that used an interior temperature sensor to more accurately climatize the cabin. This sensor was mounted overhead (near the sunroof switch) so that when the roof was open, the sensor would detect cool air-flow and call upon the system to adjust heat flow accordingly.

• Exterior temperature sensor with LCD display set in main instrument console below the speedometer to inform the driver of exterior conditions. This was delineated in Fahrenheit for US-market cars, and in Celsius for the rest of the world.

Drivetrain technologies

• Four-speed automatic transmission with a topographical sensor that monitored the vehicle's position (whether on an incline or decline) and gas pedal position. The result was an extraordinary capacity to "hold back" acceleration when coasting downhill and to maintain the S-Class' position without using the brake pedal after coming to a complete stop on a steep incline. The transmission also featured a "limp home mode" in case of electronic failure and was programmed to start in second gear so as to permit smooth, wheel spin free launches. Second gear start could be switched on and off in European models with a S/W switch to allow more performance orientated driving versus winter driving.

• The W126 carried forward the self-leveling hydropneumatic suspension of the W116 450 SEL 6.9 model. There were two versions of the self-leveling suspension for the sedan: a rear only hydraulic suspension using two nitrogen ballasts to automatically level the car, and a four-wheel hydraulic leveling system that could be set in three positions. The coupés were only available with the rear-leveling from the factory. In the US, rear-leveling was standard on both the 560 SEC and the 560 SEL, and optional on the 500 SEC and SEL. The four-wheel hydraulic leveling system was never made available for North American-market cars.

• Cruise control that used the transmission's topographical sensor to appropriately add and cut back the throttle fluidly as needed in order to maintain the desired set speed. The result was a cruise control that was free of the sudden throttle inputs and undesired downhill excess speed that plagued many contemporary cruise control systems.

Engines

In September 1985, two newly constructed six-cylinder SOHC engines, M103 (already used in the new mid-sized Mercedes-Benz W124 series), replaced the 2.8-litre DOHC M110 engines. The carburetted version was replaced by a 2.6-litre fuel injection engine, while the 3.0-litre version replaced the fuel injected M110. Also new was a 4.2-litre V8 engine, designed to replace the 3.8 litre version used in the W126 sedans, coupés, and the SL-Class. The 5.0-litre engine was modified to receive electronic ignition and electronic-mechanical fuel injection in form of the Bosch KE-jetronic system. Performance was increased to 245 hp (183 kW). An ECE version of the 5.0-litre M117 V8 engine was also available from September 1987 with a power output of 265 hp (198 kW)

The largest new engine was the 5.5-litre V8 that was a further development from the 5 litre version. An increased stroke meant it could turn out a hefty 272 hp (203 kW). There was a higher compression version available, if required, that produced 300 hp (220 kW). This version was only available without catalytic converter. But even without the catalytic converter this ECE version, as it was known, would meet the emission requirements of the European community.

A 3.0-litre inline-five cylinder turbo diesel was offered from 1981–1985 in North America. In 1986, the 300SD was replaced with the 300SDL. It was part of the second generation of W126 model lineup. The five-cylinder engine was replaced with the new inline six-cylinder engine and the engine was only offered in long-wheelbase. The new engine had 148 hp (110 kW) compared to 125 hp (93 kW) of the previous version. California specification 1986 and all 1987 cars were the first diesel cars to have a diesel particulate filter. This early implementation did not hold up under normal use, and was replaced by a standard diesel oxidization catalyst in the course of a recall.

Engine	Cyl.	Power	Torque	0–100 km/h	Maximum speed	Notes[11]
Gasoline
2.6 12V	I6	166 PS (122 kW; 164 hp)	228 N·m (168 lb·ft)		205 km/h (127 mph)	From MY 1986
2.6 12V*	I6	160 PS (118 kW; 158 hp)	220 N·m (162 lb·ft)		205 km/h (127 mph)	From MY 1986
2.8 12V carb.	I6	156 PS (115 kW; 154 hp)	223 N·m (164 lb·ft)	11.0s	200 km/h (124 mph)	MY 1980–1985
2.8 12V inj.	I6	185 PS (136 kW; 182 hp)	240 N·m (177 lb·ft)	10.0s	210 km/h (130 mph)	MY 1980–1985
3.0 12V*	I6	180 PS (132 kW; 178 hp)	255 N·m (188 lb·ft)		210 km/h (130 mph)	From MY 1986
3.0 12V	I6	188 PS (138 kW; 185 hp)	260 N·m (192 lb·ft)		210 km/h (130 mph)	From MY 1986
3.8 16V	V8	218 PS (160 kW; 215 hp)	299 N·m (221 lb·ft)		215 km/h (134 mph)	MY 1980–1981
3.8 16V	V8	204 PS (150 kW; 201 hp)	315 N·m (232 lb·ft)	9.3s	205 km/h (127 mph)	MY 1982–1985
4.2 16V*	V8	204 PS (150 kW; 201 hp)	310 N·m (229 lb·ft)		210 km/h (130 mph)	MY 1986
4.2 16V	V8	218 PS (160 kW; 215 hp)	330 N·m (243 lb·ft)	9.0s	218 km/h (135 mph)	MY 1986
4.2 16V*	V8	224 PS (165 kW; 221 hp)	325 N·m (240 lb·ft)	8.3s	218 km/h (135 mph)	From MY 1987
4.2 16V	V8	231 PS (170 kW; 228 hp)	335 N·m (247 lb·ft)	8.1s	222 km/h (138 mph)	From MY 1987
5.0 16V	V8	223 PS (164 kW; 220 hp)	365 N·m (269 lb·ft)	8.0s	220 km/h (137 mph)	From MY 1986
5.0 16V	V8	240 PS (177 kW; 237 hp)	402 N·m (297 lb·ft)		225 km/h (140 mph)	MY 1980–1981
5.0 16V	V8	231 PS (170 kW; 228 hp)	405 N·m (299 lb·ft)	8.1s	220 km/h (137 mph)	MY 1982–1985
5.0 16V	V8	245 PS (180 kW; 242 hp)	400 N·m (295 lb·ft)	7.6s	230 km/h (143 mph)	MY 1986
5.0 16V*	V8	223 PS (164 kW; 220 hp)	358 N·m (264 lb·ft)		220 km/h (137 mph)	MY 1986
5.0 16V*	V8	252 PS (185 kW; 249 hp)	390 N·m (288 lb·ft)	7.5s	230 km/h (143 mph)	From MY 1987
5.0 16V	V8	265 PS (195 kW; 261 hp)	405 N·m (299 lb·ft)	7.3s	235 km/h (146 mph)	From MY 1987
5.5 16V*	V8	242 PS (178 kW; 239 hp)	390 N·m (288 lb·ft)	7.6s	228 km/h (142 mph)	MY 1986
5.5 16V*	V8	279 PS (205 kW; 275 hp)	430 N·m (317 lb·ft)	7.2s	240 km/h (149 mph)	From MY 1987
5.5 16V	V8	272 PS (200 kW; 268 hp)	421 N·m (311 lb·ft)		250 km/h (155 mph)	MY 1986
5.5 16V RÜF	V8	299 PS (220 kW; 295 hp)	456 N·m (336 lb·ft)		250 km/h (155 mph)	From MY 1987
5.5 16V ECE	V8	299 PS (220 kW; 295 hp)	455 N·m (336 lb·ft)	6.9s	250 km/h (155 mph)	MY 1986/87
Diesel
3.0 TD	I5	125 PS (92 kW; 123 hp)	250 N·m (184 lb·ft)	15.2s	175 km/h (109 mph)	MY 1980–1985
3.0 TD	I6	150 PS (110 kW; 148 hp)	273 N·m (201 lb·ft)	12.5s	195 km/h (121 mph)	MY 1986/87
3.5 TD	I6	136 PS (100 kW; 134 hp)	310 N·m (229 lb·ft)	13.0s	175 km/h (109 mph)	MY 1990/91
* = Catalyst version

Special variants

Popular tuners

• AMG offered body kits for all W126 models, as well as a widebody kit for the coupé. AMG also offered many levels of engine tuning, but was most famous for the DOHC 6.0 litre engine, based on the original 117.968 engine. Also offered was a Gleason Torsen differential in varying ratios, manual transmission (extremely rare), and various TV/radio consoles.
• Transco Bremen offered a stretch limousine version called the "1000 SEL".^[12]

Armored models

Like the current model S-Guard, specially modified W126 S-Class models were produced for the transport of dignitaries and world leaders. Among the modifications made included a wheelbase stretch, bulletproof glass, and armored body panels.

U.S. grey market

The 500 SEL has an interesting place in U.S. automotive history, since American demand for this particular car drove the establishment of a large grey market. The detuned, yet very expensive US specification 380 SE/SEL/SEC was underpowered, according to contemporary reports, and fuelled demand for the more powerful version available in the rest of the world. Approximately 22,000 units per year of grey market Mercedes-Benz (including the 500 SE/SEL) were sold in the early 1980s, according to contemporary reports in the Los Angeles Times.^[13]

Racing

Two AMG-modified 500 SEC cars raced at the 1989 24 Hours of Spa. Both cars failed to finish, with one suffering gearbox issues, while other had issues with the rear axle.^[14]

Awards

The W126 S-Class was a champion in the luxury car market, dominating worldwide sales during its production run. At the same time, it also achieved several awards during its production period. The W126 model 380 SE was the Wheels Magazine Car of the Year in 1981,^[4] the W126 was awarded the U.S. Highway Loss Data Institute "Safest Passenger Car of the Year" in 1988 and 1989,^[1] and the W126 was the third-ranked luxury vehicle in J.D. Power's 1990 Initial Quality Survey (IQS).^[15] In 1987, 1988, 1989, and 1990, with the W126 S-Class leading its sales, Mercedes-Benz received the highest customer ratings in the J.D. Power Sales Satisfaction Index.^[16]

Legacy

The W126 S-Class's twelve-year production run was longer than any S-Class before or since, and following the debut of the W140 S-Class in 1991, the additional two years of production in South Africa was a testament to the W126's popularity in the export market. Many W126s have been prominently featured in films long after production ended.^[17]

References

Notes

Bibliography

General

Workshop manuals

External links

Wikimedia Commons has media related to Mercedes-Benz W126.

Wikimedia Commons has media related to Mercedes-Benz C126.

• The unofficial W126 page – history and details of the W126
• Fuenfkommasechs.de – German website with vast information on development, model history, engines and innovations

v t e « previous — Mercedes-Benz road car timeline, 1990s–present
Model	Body	1990s										2000s										2010s
		0	1	2	3	4	5	6	7	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3
A	Hatch									W168							W169							W176
B																	W245							W246
C	Saloon	W201			W202								W203							W204
	Estate							S202					S203							S204
E	Saloon	W124					W210							W211							W212
	Limousine	V124																				V212
	Estate	S124						S210							S211							S212
S	Saloon	W126	W140								W220							W221							W222
	Limousine	V126	V140								V220							V221							V222
	Pullman								VF140			VF220										VF221
CLA	Coupé																								C117
CLC / C													CL203							CL203				C204
CLK / E		C124						C208							C209						C207
	Cabriolet		A124						A208							A209						A207
CLS	Coupé																	W219					W218
CL		C126		C140							C215							C216
SLK	Roadster									R170							R171					R172
SL		R129													R230									R231
SLS	Coupé																					C197
	Roadster																						R197
SLR	Coupé														C199
	Roadster																		R199
	Speedster																				Z199
Vaneo	MPV													W414
R																		W251
GLK	SUV																			X204
M										W163								W164						W166
GL																		X164							X166
G		W460/461
		W463
Citan	LCV																								W415
Vito		MB100						W638								W639
Sprinter		T1					W901 - W905											NCV3
Vario		T2						W670
Model	Body	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3
		1990s										2000s										2010s

v t e Mercedes-Benz CL-Class lineage, 1950s–present W187 (1951) W180 (1956) W128 (1958) W111/W112 (1961) C107 (1971) C126 (1981) C140 (1992) C215 (1999) C216 (2006)

v t e Mercedes-Benz S-Class lineage, 1950s–present W187 (1951) W180 (1955) W128 (1958) W111 (1959) W112 (1961) W108 (1965) W116 (1972) W126 (1979) W140 (1991) W220 (1999) W221 (2006) W222 (2014)