The Mercedes-Benz CLS 250 CDI, produced between March 2011 and July 2014, was a diesel-powered variant of the C218 CLS-Class coupe. Positioned as a more fuel-efficient option within the CLS range, it aimed to deliver a blend of luxury, performance, and economy. This model occupied a mid-range position in the CLS lineup, slotting below the more powerful CLS 350 and CLS 550, and above any potential base models offered in certain markets. The 250 CDI was a significant offering for European markets where diesel engines were highly favored, providing a sophisticated grand touring experience with reduced running costs. It was built on the 218 platform, sharing its underpinnings with other Mercedes-Benz models of the era.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | CLS |
| Generation | CLS coupe (C218) |
| Type (Engine) | CLS 250 CDI (204 Hp) 7G-TRONIC PLUS |
| Start of production | March, 2011 |
| End of production | July, 2014 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 4 |
| Doors | 4 |
| Fuel consumption (economy) – urban (NEDC) | 6.4-6.5 l/100 km (36.8 – 36.2 US mpg, 44.1 – 43.5 UK mpg, 15.6 – 15.4 km/l) |
| Fuel consumption (economy) – extra urban (NEDC) | 4.4-4.5 l/100 km (53.5 – 52.3 US mpg, 64.2 – 62.8 UK mpg, 22.7 – 22.2 km/l) |
| Fuel consumption (economy) – combined (NEDC) | 5.1-5.3 l/100 km (46.1 – 44.4 US mpg, 55.4 – 53.3 UK mpg, 19.6 – 18.9 km/l) |
| CO2 emissions (NEDC) | 134-138 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 7.5 sec |
| Acceleration 0 – 62 mph | 7.5 sec |
| Acceleration 0 – 60 mph | 7.1 sec |
| Maximum speed | 242 km/h (150.37 mph) |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 8.4 kg/Hp, 119.3 Hp/tonne |
| Weight-to-torque ratio | 3.4 kg/Nm, 292.4 Nm/tonne |
| Power | 204 Hp @ 4200 rpm |
| Power per litre | 95.2 Hp/l |
| Torque | 500 Nm @ 1600-1800 rpm (368.78 lb.-ft. @ 1600-1800 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | OM 651.924 |
| Engine displacement | 2143 cm3 (130.77 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 83 mm (3.27 in.) |
| Piston Stroke | 99 mm (3.9 in.) |
| Compression ratio | 16.2:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | BiTurbo, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 6.5 l (6.87 US qt | 5.72 UK qt) |
| Coolant | 10.4 l (10.99 US qt | 9.15 UK qt) |
| Kerb Weight | 1710 kg (3769.9 lbs.) |
| Max. weight | 2270 kg (5004.49 lbs.) |
| Max load | 560 kg (1234.59 lbs.) |
| Trunk (boot) space – minimum | 520 l (18.36 cu. ft.) |
| Fuel tank capacity | 59 l (15.59 US gal | 12.98 UK gal) |
| Max. roof load | 100 kg (220.46 lbs.) |
| Length | 4940 mm (194.49 in.) |
| Width | 1881 mm (74.06 in.) |
| Width including mirrors | 2075 mm (81.69 in.) |
| Height | 1416 mm (55.75 in.) |
| Wheelbase | 2874 mm (113.15 in.) |
| Front track | 1596 mm (62.83 in.) |
| Rear (Back) track | 1626 mm (64.02 in.) |
| Front overhang | 901 mm (35.47 in.) |
| Rear overhang | 1165 mm (45.87 in.) |
| Drag coefficient (Cd) | 0.26 |
| Minimum turning circle (turning diameter) | 11.27 m (36.98 ft.) |
| 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 | 7 gears, automatic transmission G-TRONIC PLUS |
| Front suspension | Coil spring, Independent multi-link suspension, Transverse stabilizer, Air Suspension – Optional |
| Rear suspension | Independent multi-link spring suspension with stabilizer, Air Suspension – Optional |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Electric Steering |
| Tires size | Front wheel tires: 245/45 R17; 255/40 R18; 255/35 R19Rear wheel tires: 245/45 R17; 255/40 R18; 285/35 R18; 285/30 R19 |
| Wheel rims size | Front wheel rims: 8J x 17; 8.5J x 18; 8.5J x 19Rear wheel rims: 8J x 17; 8.5J x 18; 9.5J x 18; 9.5J x 19 |
Powertrain & Engine Architecture
The CLS 250 CDI was powered by the OM651.924, a 2.1-liter inline-four diesel engine. This engine was a mainstay in the Mercedes-Benz lineup, known for its robust construction and efficiency. The OM651 featured a sophisticated common-rail direct injection system, delivering fuel at extremely high pressures for optimized combustion. A bi-turbocharger setup, utilizing a small and a large turbocharger, minimized turbo lag and provided a broad torque curve. The smaller turbocharger spooled up quickly at low engine speeds, while the larger turbo took over at higher RPMs for sustained power. The engine also incorporated an intercooler to further enhance performance by cooling the intake air. The 7G-TRONIC PLUS automatic transmission, a seven-speed unit, was standard. This transmission was renowned for its smooth shifting and efficiency, contributing to the overall refinement of the CLS 250 CDI. It featured a torque converter lock-up clutch to minimize slippage and improve fuel economy.
Driving Characteristics
The 204 horsepower and 368 lb-ft of torque delivered by the CLS 250 CDI provided a comfortable and capable driving experience. While not overtly sporty, the engine offered ample power for highway cruising and overtaking. The 7G-TRONIC PLUS transmission was programmed for smooth, almost imperceptible gear changes, prioritizing comfort over aggressive shifts. Compared to the more powerful CLS 350, the 250 CDI felt less urgent in acceleration, taking 7.5 seconds to reach 62 mph. However, the substantial low-end torque of the diesel engine made it feel responsive in everyday driving situations. The automatic transmission’s gear ratios were optimized for fuel efficiency, keeping engine speeds relatively low during cruising. Compared to a manual transmission equipped CLS, the automatic offered less driver engagement but greater convenience.
Equipment & Trim Levels
The CLS 250 CDI typically came well-equipped, reflecting its positioning as a luxury coupe. Standard features included leather upholstery, automatic climate control, a multi-function steering wheel, and a high-end audio system. Optional extras included features like a panoramic sunroof, premium sound systems (such as Harman Kardon), adaptive cruise control, and various driver assistance systems. Interior trim options allowed for customization, with choices in wood veneers and aluminum accents. The dashboard layout was typical of Mercedes-Benz at the time, emphasizing a clean and elegant design. The availability of optional air suspension further enhanced ride comfort.
Chassis & Braking
The CLS 250 CDI utilized a sophisticated suspension system designed to balance comfort and handling. The front suspension featured a multi-link setup with coil springs and a transverse stabilizer bar. The rear suspension employed an independent multi-link design with a stabilizer bar. Optional air suspension was available, providing adjustable ride height and damping for enhanced comfort and control. Braking duties were handled by ventilated discs at the front and solid discs at the rear. Anti-lock braking system (ABS) was standard, ensuring safe and controlled stopping power. The steering system was a rack-and-pinion setup with electric power assistance.
Market Reception & Comparison
The CLS 250 CDI was generally well-received by automotive critics, particularly for its fuel efficiency and refined driving experience. It was praised for offering a luxurious and comfortable grand touring experience with significantly lower running costs than its gasoline-powered siblings. Compared to the CLS 350, the 250 CDI offered comparable levels of luxury and technology but with a more economical engine. The CLS 250 CDI’s fuel economy was a key selling point, achieving combined figures of around 46-44 US mpg. Reliability was generally good, although diesel engines can be more susceptible to issues with the fuel injection system and particulate filter over time.
Legacy
The CLS 250 CDI has proven to be a relatively reliable vehicle in the used car market. The OM651 engine is known for its durability, provided it has been properly maintained. Common maintenance items include regular oil changes, fuel filter replacements, and inspection of the turbocharger and particulate filter. Today, the CLS 250 CDI represents a compelling value proposition for buyers seeking a luxurious and fuel-efficient coupe. Its blend of style, comfort, and economy continues to appeal to a wide range of drivers. While newer models offer more advanced technology, the C218 CLS 250 CDI remains a stylish and capable grand tourer.
