2018 Audi A6 Diesel 40 TDI Review: Efficiency, Space, Tech

The 2018 Audi A6 diesel marks a significant evolution in the executive sedan segment, blending superior fuel efficiency, enhanced space, and engaging driving characteristics into one refined package. Building on the platform of the acclaimed A7, this model delivers a compelling alternative to rivals like the BMW 5 Series and Mercedes E-Class.

Design and Dimensions: Bigger and Bolder

The fifth-generation Audi A6 adopts a more imposing stance with increased dimensions that enhance its road presence. Measuring longer and wider than its predecessor, it offers a sleek profile accented by the brand’s signature Singleframe grille, adaptive LED headlights, and distinctive LED tail lights with dynamic patterns.

Exterior updates include sharper lines and a lower roofline, contributing to improved aerodynamics. Available in various trims, from entry-level Sport to premium S Line, the A6 diesel emphasizes elegance without excess aggression. Wheel options range from 17-inch alloys to 20-inch designs, balancing style and ride comfort.

• Larger footprint: Provides better stability and presence on highways.
• LED lighting suite: Ensures superior visibility and modern aesthetics.
• Color choices: Multiple metallic and pearlescent finishes for personalization.

Powertrain Excellence: The Efficient 40 TDI

At the heart of this review is the 40 TDI variant, powered by a 2.0-liter four-cylinder turbo diesel engine producing 201 horsepower and substantial torque from low revs. Paired with a smooth seven-speed S tronic dual-clutch transmission, it accelerates from 0-62mph in around 8.1 seconds, feeling peppier than figures suggest due to a lighter curb weight.

The mild-hybrid system, featuring a 12-volt belt-driven starter-generator, aids efficiency by enabling smoother stop-start functionality and coasting recuperation. Real-world tests indicate over 50mpg on mixed routes, with a 63-liter tank enabling ranges exceeding 600 miles.

Quattro all-wheel drive, standard on many markets, enhances traction without compromising agility. Drive select modes—Efficiency, Comfort, Dynamic—allow tailoring throttle response, steering weight, and suspension firmness.

Driving Dynamics: Balanced and Engaging

Behind the wheel, the A6 diesel prioritizes composure over outright sportiness, yet surprises with its natural feel. The suspension, tuned for the lighter diesel, absorbs imperfections smoothly while maintaining body control in corners. Steering is precise and feedback-rich, especially without the complex aids found in V6 models.

On twisty roads, quattro grips tenaciously, enabling confident progress. The cabin remains serene at speed, with minimal diesel clatter after warmup. Dynamic mode sharpens shifts and tightens handling, making it a match for sportier rivals.

• Front-wheel drive base: Adequate for most, with low running costs.
• Quattro upgrade: Superior wet-weather poise and stability.
• Mild-hybrid boost: Reduces fuel use during cruising.

Interior Refinement: Tech-Laden Sanctuary

Step inside to a cabin of impeccable quality, dominated by dual touchscreens for the MMI infotainment system. The upper 10.1-inch display handles navigation and media, while the lower 8.6-inch unit manages climate and vehicle functions. Haptic feedback ensures intuitive use.

The optional Virtual Cockpit—a 12.3-inch customizable digital cluster—displays crisp graphics for speed, maps, or media. Materials blend soft leather, wood inlays, and aluminum accents, creating a premium ambiance.

Rear space impresses with 17mm extra legroom and generous headroom, accommodating adults comfortably. The 530-liter boot is practical, though mildly compromised by hybrid batteries.

Safety and Technology Features

Audi packs the A6 with advanced driver aids derived from the A8 flagship. Standard pre-sense front collision warning mitigates impacts effectively, earning high marks in tests.

Adaptive cruise control, lane-keeping assist, and traffic jam assist operate seamlessly. Parking is aided by 360-degree cameras and self-parking tech. Connectivity includes Apple CarPlay, Android Auto, and wireless charging.

Competitor Comparison: How It Stacks Up

Against the BMW 520d, the A6 offers superior rear space and tech but slightly less rear-drive dynamism. The Mercedes E300de prioritizes plug-in efficiency, yet lacks the A6’s diesel refinement. Pricing starts competitively, with strong residuals.

Ownership Costs and Practicality

Running costs shine with low BIK ratings for company cars and extended service intervals. Warranty covers three years/60,000 miles, with options for prepaid maintenance. Resale values hold firm due to Audi’s reputation.

Trims like SE emphasize value with alloys, sat-nav, and part-leather seats. S Line adds sportier styling and matrix LED lights.

Pros and Cons at a Glance

• Pros: Exceptional economy, spacious interior, refined drive, cutting-edge tech.
• Cons: Boot slightly smaller than some rivals, screen-heavy controls may divide opinions.

Frequently Asked Questions (FAQs)

Is the 2018 Audi A6 diesel reliable?

Yes, it benefits from Audi’s proven diesel tech and mild-hybrid system, with strong owner satisfaction scores.

What’s the real-world fuel economy?

Expect 48-55mpg depending on conditions, outperforming petrol variants.

Does it have Apple CarPlay?

Standard on higher trims; optional on base models via MMI Navigation Plus.

How does quattro affect handling?

It boosts grip and stability, ideal for all-weather driving without harshness.

Is rear space family-friendly?

Absolutely, with limo-like legroom and ISOFIX points.

Final Verdict: A Top Contender

The 2018 Audi A6 diesel, particularly the 40 TDI, redefines executive travel with its blend of efficiency, luxury, and poise. Ideal for long-distance cruisers seeking value without compromise, it earns a strong recommendation.