Peugeot 508 I (8D) (2010 – 2018)

Reliability score : 6.5/10

The Peugeot 508 Generation I (internal code 8D for the sedan, 8E for the SW estate) was introduced to replace both the 407 and the flagship 607. It marked a significant step up in perceived quality, cabin space, and driving dynamics for the brand. A major facelift (Phase 2) occurred in 2014, bringing a more vertical grille, full LED headlights on higher trims, an updated touchscreen infotainment system, and crucially, Euro 6 compliant engines. Petrol Engine Focus: The early petrol lineup was heavily reliant on the 'Prince' engine family (EP6), co-developed with BMW. The pre-facelift 1.6 THP 156 hp is notorious for severe reliability issues. However, the post-facelift 1.6 THP 165 hp (Euro 6) resolved the vast majority of these flaws, making it a highly recommendable choice. While diesel dom

✅ Strengths

Excellent chassis balance: a perfect mix of comfort and dynamic handling.
High-quality interior materials, especially on Allure, Feline, and GT trims.
The 1.6 THP 165 (post-2014) is a fantastic, refined, and reliable petrol engine.
The EAT6 automatic gearbox (post-2014) is smooth and reliable (Aisin-sourced).
Huge boot space in the SW (estate) version.
Outstanding reliability of the older 2.0 HDi (140/163 hp) diesel engines.

⚠️ Weaknesses

Catastrophic reliability of the pre-2014 1.6 THP 156 petrol engine.
Widespread and expensive AdBlue system failures on BlueHDi models.
The BMP6 / ETG6 automated manual gearboxes are jerky, slow, and prone to clutch wear.
Lack of interior storage spaces (tiny cup holders, small door bins).
Water ingress in the boot of the sedan when opening the lid in the rain.
Outdated and laggy infotainment systems, even on Phase 2 models.

🎯 Verdict

The Peugeot 508 I is a superb long-distance cruiser with an excellent chassis. However, if you are looking for a petrol version, you must navigate the lineup with extreme caution. Rule of thumb for petrol buyers: Absolutely avoid the pre-2014 1.6 THP 156 hp unless it has a meticulously documented history of timing chain and HPFP replacements. Instead, focus entirely on the post-facelift 1.6 THP 165 hp (2014-2018). It is a vastly superior, reliable, and refined engine, especially when paired with the EAT6 automatic gearbox. If you are in a market where the 2.0L or 2.3L naturally aspirated engines are available, they are bulletproof, albeit less efficient.