Audi A8 D4 (4H) (2009 – 2017)

Reliability score : 7.8/10

The third-generation Audi A8 (code name D4 / Typ 4H) represents the pinnacle of luxury and technology for the brand with the four rings during this period. Based on the Audi Space Frame (ASF) aluminum structure, it manages to keep its weight down despite its imposing size. Equipped as standard with Quattro AWD (except on the rare hybrid version) and the excellent 8-speed ZF automatic gearbox (Tiptronic), it offers an exceptional compromise between supreme comfort and dynamism. A major facelift took place at the end of 2013 (Model Year 2014), introducing notably Matrix LED headlights, dynamic turn signals, and revised engines to meet the Euro 6 standard. On the used market, the diesel versions (3.0 TDI and 4.2 TDI) are highly praised for their massive torque and range, but require rigorous

✅ Strengths

Exceptional interior finish quality, remarkable aging of materials
Top-tier soundproofing (especially with acoustic glazing)
Smooth, responsive, and very reliable 8-speed ZF automatic gearbox
Efficiency and driving pleasure of the 3.0 TDI V6 engine
Imperial traction thanks to the standard Quattro system
Comfort of the adaptive air suspension

⚠️ Weaknesses

Supercar-level maintenance and repair costs on the V8/W12
Imposing size (5.14m in short version, 5.27m in L version) difficult in the city
Rapid wear of tires and brakes (weight often exceeding 2 tons)
MMI infotainment system that has aged technologically (before the facelift)
Very complex mechanical accessibility (especially on the 4.2 TDI and W12)

🎯 Verdict

The Audi A8 D4 is a formidable traveling machine, particularly brilliant in its diesel versions. The 3.0 TDI V6 is the rational choice: it offers more than adequate performance, controlled consumption, and very decent reliability if maintenance has been followed. The 4.2 TDI is a monster of driving pleasure, but its maintenance costs in the event of a glitch (especially the timing chain) can ruin its owner. On the petrol side, the 3.0 TFSI is the most well-rounded. The 4.0 TFSI (A8 and S8) is magical but imperatively requires that the turbo screen issue has been resolved. Avoid the 2.0 TFSI Hybrid version, whose mechanical (EA888) and electrical reliability is hazardous. In all cases, plan for a substantial maintenance budget: wear parts (brakes, tires, suspension arms) and electronics are expensive.

Common issues

Filtre à Particules (FAP/DPF) encrassé ou défectueux Medium

🔧 150 000 – 250 000 km

💶 1 200 – 2 500 € (remplacement)

Privilégier les longs trajets réguliers pour favoriser la régénération du FAP.

Vanne EGR (Exhaust Gas Recirculation) encrassée ou défectueuse Medium

🔧 100 000 – 200 000 km

💶 400 – 900 €

Un nettoyage préventif peut prolonger sa durée de vie, utiliser carburant de qualité.

Turbocompresseur (usure ou défaillance de l'actuateur) High

🔧 180 000 – 250 000 km

💶 1 500 – 3 000 €

Respecter les temps de chauffe et de refroidissement, vidanges régulières avec huile adaptée.

Défaillance de la suspension pneumatique (compresseur ou amortisseurs) Medium

🔧 120 000 – 200 000 km

💶 800 – 2 000 € (par élément)

Vérifier l'assiette du véhicule et écouter les bruits anormaux, surtout au démarrage.

Estimated maintenance costs

Oil change	£110 – 200
Timing chain	£2 000 – 3 800 (si nécessaire, non planifié)
Complete brakes	£600 – 1 000
Estimated annual budget	£850 – 1 700

Indicative estimates (independent garage, UK market). Prices vary by region and year.