Mercedes S350 CDI Review: Diesel Luxury, Efficiency, Safety

The Mercedes S350 CDI stands as a testament to engineering excellence in the luxury sedan segment. This diesel-powered variant of the iconic S-Class delivers a compelling mix of refined performance, impressive efficiency, and state-of-the-art safety features, making it ideal for executives and long-haul drivers alike.

Powertrain and Performance Excellence

At the heart of the S350 CDI lies a 3.0-liter V6 turbo diesel engine producing 235 horsepower and a substantial 398 lb-ft of torque. This setup propels the hefty two-and-a-half-ton vehicle from 0 to 60 mph in approximately 7.5 seconds, offering smooth and effortless acceleration. Paired with a seven-speed automatic transmission controlled via a steering column stalk, gear shifts are seamless, contributing to a hushed cabin experience where diesel clatter is minimal—just a subtle hiss accompanies the surge of power.

On the highway, the engine shines with its torque-rich character, enabling confident overtaking without needing high revs. Real-world testing confirms its prowess, with 0-60 mph times around 7.0 seconds in all-wheel-drive configurations, matching petrol counterparts in launch speed despite the diesel’s focus on low-end grunt. Top speeds exceed 150 mph, though the car’s luxury ethos prioritizes composure over outright velocity.

Fuel Efficiency and Environmental Credentials

One of the S350 CDI’s standout traits is its fuel economy, officially rated at around 37 mpg combined, with real-world figures often hitting 26-30 mpg on long cruises, even at elevated speeds. Emissions have been refined to 199-204 g/km CO2 through aerodynamic under-body panels, low-rolling-resistance tires, and a clever system that disengages the transmission at stops to save fuel. This makes it a smarter choice for high-mileage users compared to petrol or hybrid siblings, boasting ranges over 1,000 km per tank.

This table highlights how the diesel edges out rivals in efficiency while maintaining luxury credentials.

Dynamic Handling and Ride Quality

Despite its imposing 17-foot length, the S350 CDI handles with surprising poise. Adaptive air suspension and damping systems iron out road imperfections, delivering a sublime ride on motorways even in adverse weather. The chassis feels firm yet compliant, avoiding the floaty ‘boat-like’ sensation of older flagships, with precise steering that inspires confidence on twisty roads.

Crosswind stabilization is a highlight, using stability control to counter gusts by adjusting spring loads, proven effective in controlled tests. Braking requires 181 feet from 70 mph, respectable for the weight, though not class-leading. All-wheel drive enhances traction, making it stable in rain or on inclines.

Interior Luxury and Comfort Features

Step inside, and the S350 CDI envelops occupants in opulent quietude. Seats offer infinite adjustability, active bolstering, and massage functions for ultimate comfort on extended journeys. Materials feel premium—aluminum-milled switchgear and sumptuous leather create a sanctuary quieter than many hybrids. Rear passengers enjoy limo-like space, with effortless access and serene isolation from road noise.

Infotainment includes a night-view assist system using infrared for enhanced visibility beyond headlights, displaying clear grayscale images and pedestrian alerts. The cockpit shrinks around the driver, with intuitive controls and a speedometer that adapts for night view.

• Key Comfort Highlights:
• Multi-adjustable seats with massage and ventilation
• Nearly silent cabin at highway speeds
• Expansive rear legroom for chauffeured travel
• Adaptive climate control for all zones

Advanced Safety Innovations

Safety defines the S-Class legacy, and the S350 CDI advances it further. Adaptive High Beam Assist prevents dazzling oncoming traffic, Attention Assist monitors steering for drowsiness via body movement analysis, and Lane Keeping Assist vibrates the wheel to correct drifts. These semi-autonomous aids reduce fatigue on long drives.

Additional tech like blind-spot monitoring and adaptive cruise control (flawless in heavy rain) cement its status as a safety benchmark. The diesel’s stability systems integrate seamlessly, enhancing control in emergencies.

Purchase Considerations and Pricing

New, the S350 CDI commanded around £61,940, packed with standard luxuries. Used models from 2011-2012 eras offer bargains, especially diesels delivering 40+ mpg reliability. Maintenance suits Mercedes specialists, with the robust Bluetec engine proving durable for high-mileage use.

Compared to rivals like BMW 7 Series or Audi A8, it excels in ride refinement and torque delivery, though petrol fans may prefer snappier acceleration.

Real-World Ownership Insights

Owners praise its highway smoothness, achieving 30+ mpg at 80 mph, with minimal diesel vibe. It’s a ‘best car in the world’ for some, blending firmness and luxury. Drawbacks include hefty stopping distances and width on narrow lanes. For efficiency-focused luxury, it’s unmatched.

Frequently Asked Questions (FAQs)

Is the S350 CDI fuel-efficient for its size?

Yes, it achieves up to 37 mpg combined, outperforming many petrol luxury sedans.

How does the diesel engine sound inside?

Extremely refined—mostly a hush with torque on tap, far from traditional diesel rattle.

What safety features stand out?

Attention Assist, Lane Keeping, crosswind stabilization, and night vision are game-changers.

Is it good for long motorway trips?

Exceptional stability, low noise, and 1,000+ km range make it ideal.

What’s the maintenance like?

Reliable with proper care; diesel longevity suits high-mileage drivers.

Why Choose the S350 CDI?

In a sea of luxury sedans, the Mercedes S350 CDI distinguishes itself with diesel efficiency without sacrificing opulence or tech. It’s the rational yet indulgent choice for discerning drivers.