The Mercedes-Benz 560 SEC, part of the C126 series facelift produced from September 1987 to October 1991, represented the pinnacle of luxury coupe design for its time. Positioned as the top-of-the-line variant within the C126 coupe range, it offered a significant step up in performance and refinement compared to the 380 SEC and 420 SEC models. The 560 SEC was a statement vehicle, embodying Mercedes-Benz’s commitment to engineering excellence and opulent comfort. It was primarily marketed towards affluent buyers seeking a grand touring experience, and was a popular choice among celebrities and executives.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | S-class |
| Generation | S-class Coupe (C126, facelift 1985) |
| Type (Engine) | 560 SEC V8 CAT (279 Hp) Automatic |
| Start of production | September, 1987 |
| End of production | October, 1991 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 4 |
| Doors | 2 |
| Fuel consumption (urban) | 18 l/100 km (13.1 US mpg, 15.7 UK mpg, 5.6 km/l) |
| Fuel consumption (extra urban) | 11.4 l/100 km (20.6 US mpg, 24.8 UK mpg, 8.8 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 7.2 sec |
| Acceleration 0 – 62 mph | 7.2 sec |
| Acceleration 0 – 60 mph | 6.8 sec |
| Maximum speed | 240 km/h (149.13 mph) |
| Weight-to-power ratio | 5.5 kg/Hp, 181.2 Hp/tonne |
| Weight-to-torque ratio | 3.6 kg/Nm, 279.2 Nm/tonne |
| Power | 279 Hp @ 5200 rpm |
| Power per litre | 50.3 Hp/l |
| Torque | 430 Nm @ 3750 rpm (317.15 lb.-ft. @ 3750 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M 117 E 56 / 117.968 |
| Engine displacement | 5547 cm3 (338.5 cu. in.) |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 96.5 mm (3.8 in.) |
| Piston Stroke | 94.8 mm (3.73 in.) |
| Compression ratio | 10:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | SOHC |
| Engine oil capacity | 8 l (8.45 US qt | 7.04 UK qt) |
| Coolant | 13.5 l (14.27 US qt | 11.88 UK qt) |
| Kerb Weight | 1540 kg (3395.12 lbs.) |
| Max. weight | 2220 kg (4894.26 lbs.) |
| Max load | 680 kg (1499.14 lbs.) |
| Fuel tank capacity | 90 l (23.78 US gal | 19.8 UK gal) |
| Length | 4935 mm (194.29 in.) |
| Width | 1828 mm (71.97 in.) |
| Height | 1402 mm (55.2 in.) |
| Wheelbase | 2845 mm (112.01 in.) |
| Front track | 1555 mm (61.22 in.) |
| Rear track | 1527 mm (60.12 in.) |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels of the vehicle. |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 4 gears, automatic transmission |
| Front suspension | Double wishbone |
| Rear suspension | Threaded twist beam |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Power steering | Hydraulic Steering |
| Tires size | Front wheel tires: 215/65 R15Rear wheel tires: 215/65 R15 |
| Wheel rims size | Front wheel rims: 7J x 15Rear wheel rims: 7J x 15 |
Powertrain & Engine Architecture
The heart of the 560 SEC is the M117.968 5.6-liter V8 engine. This engine, a descendant of the long-running M117 family, was renowned for its smoothness and durability. It featured a single overhead camshaft (SOHC) design per bank, operating two valves per cylinder. Bosch K-Jetronic fuel injection, a mechanical system known for its reliability, delivered fuel to the cylinders. The catalytic converter (“CAT” in the model designation) was a crucial addition for meeting increasingly stringent emissions regulations. The engine produced 279 horsepower at 5200 rpm and 430 Nm (317 lb-ft) of torque at 3750 rpm. Paired with a four-speed automatic transmission (typically the 722.3 series), the powertrain provided a balance of performance and ease of use. The transmission was designed for smooth shifts and reliable operation, though it lacked the sophistication of later electronically controlled automatics.
Driving Characteristics
The 560 SEC offered a distinctly grand touring experience. While not a sports car, the 5.6-liter V8 provided ample power for effortless cruising and confident overtaking. Acceleration from 0 to 60 mph took around 6.8 seconds, respectable for the late 1980s. The automatic transmission, while smooth, wasn’t particularly quick-shifting, and the gear ratios were geared towards comfortable highway driving rather than aggressive acceleration. Compared to the 420 SEC, the 560 SEC offered a noticeable increase in performance, feeling significantly more responsive. The heavier engine did slightly impact handling balance, but the well-tuned suspension minimized body roll and provided a comfortable ride. The steering, while hydraulic, felt somewhat heavy and lacked the precision of more modern systems.
Equipment & Trim Levels
The 560 SEC came standard with a comprehensive list of luxury features. Leather upholstery was standard, along with power-adjustable front seats with memory function. Climate control, a premium sound system, and power windows and locks were also included. The interior trim was typically finished in wood veneer, adding to the sense of opulence. Optional extras included a sunroof, heated seats, and a more advanced audio system. The exterior featured distinctive chrome trim and alloy wheels. The overall aesthetic was one of understated elegance, reflecting Mercedes-Benz’s design philosophy of the time.
Chassis & Braking
The C126 coupe chassis utilized a double wishbone suspension at the front and a threaded twist beam rear axle. This setup provided a good balance of ride comfort and handling. The 560 SEC featured ventilated disc brakes at all four corners, providing ample stopping power. An Anti-lock Braking System (ABS) was standard, enhancing safety. The steering system employed a cone worm and recirculation ball mechanism, offering a substantial feel but lacking the directness of rack-and-pinion steering. The tires were typically 215/65 R15, providing a good compromise between comfort and grip.
Market Reception & Comparison
The 560 SEC was generally well-received by automotive critics. It was praised for its luxurious interior, smooth ride, and powerful engine. However, some critics noted the relatively high price and the somewhat dated technology compared to newer rivals. Compared to the 420 SEC, the 560 SEC offered a significant performance upgrade, but at a higher cost. Fuel economy was a concern, with the 5.6-liter V8 consuming a considerable amount of gasoline. Reliability was generally good, but maintenance costs could be high due to the complexity of the engine and the age of the vehicle.
Legacy
The Mercedes-Benz 560 SEC remains a highly sought-after classic car today. Its combination of luxury, performance, and timeless design has made it a favorite among collectors and enthusiasts. The M117 engine is known for its durability, and well-maintained examples can still provide years of reliable service. However, finding parts can be challenging, and maintenance costs can be significant. The 560 SEC represents a high point in Mercedes-Benz coupe design, and it continues to be admired for its engineering excellence and enduring style. The car’s value has steadily increased in recent years, reflecting its growing desirability in the classic car market.
