Audi A6 C8 (4K) (2018 – 2025)

Reliability score : 7.4/10

The Audi A6 C8 (internal designation 4K) represents the eighth generation of Audi's executive class. Launched in 2018, it brought a massive leap in digitalization, featuring the dual-screen MMI Touch Response system and standardizing Mild Hybrid Electric Vehicle (MHEV) technology across almost the entire range. While North America and Asia shifted heavily towards petrol (TFSI), the European market retained a strong focus on diesel (TDI) powertrains, highly favored by fleet operators and high-mileage drivers. The C8 generation is praised for its exceptional refinement, build quality, and highway cruising capabilities. However, its complex 48V electrical architecture (specifically on V6 models) and early software glitches have been notable pain points. A mild facelift was introduced for the

✅ Strengths

Exceptional interior build quality and material selection
Class-leading acoustic insulation and highway refinement
Highly efficient 2.0 TDI engine for long-distance driving
Quattro AWD system provides outstanding all-weather grip
Spacious cabin and practical Avant (estate) body style

⚠️ Weaknesses

Widespread and critical failures of the 48V BSG on V6 models
Noticeable throttle/gearbox lag on early V6 TDI models
Over-reliance on touchscreens can be distracting while driving
High maintenance and repair costs, especially for electrical issues
Intrusive ADAS (Advanced Driver Assistance Systems), particularly Pre-Sense

🎯 Verdict

The Audi A6 C8 is a technological tour de force and one of the best highway cruisers in its class. If you are looking for a diesel, the 2.0 TDI (40 TDI) is the smartest and most reliable choice, offering excellent economy without the catastrophic 48V electrical risks of the larger engines. The 3.0 V6 TDI (50 TDI) is a masterpiece of torque and refinement, but it comes with a massive caveat: the 48V Belt Starter Generator (BSG) failure is a matter of 'when', not 'if', unless it has already been replaced with the latest revised part. If buying a V6 (TDI or TFSI), an extended warranty is strongly advised. Always ensure all software updates and recalls (especially the gateway module) have been performed.