MINI Mini IV (J01) (2023 – Présent)

Reliability score : 8.7/10

MINI Cooper Generation IV (J01 / F66) The fourth generation of the iconic MINI Cooper marks a radical shift in the brand's history, splitting the model into two distinct platforms under the same design language. The J01 designates the all-new, fully electric model co-developed with Great Wall Motor (Spotlight Automotive) and initially built in China. Meanwhile, the F66 designates the internal combustion engine (ICE) models, which are heavily updated versions of the previous F56 platform, built in Oxford, UK. CRITICAL NOTE REGARDING DIESEL: As requested, the focus was placed on the diesel powertrain. However, as an independent expert, I must clarify that MINI has completely discontinued diesel engines for the 4th generation. The last diesel MINIs (Cooper D / SD) were phased out during the p

✅ Strengths

Exceptional 9.4-inch circular OLED display (industry first).
Vastly improved EV range on the J01 (up to 402 km WLTP for the SE) compared to the previous generation.
Retention of the highly reliable BMW B38 and B48 petrol engines for the F66.
High-quality interior materials with a unique, sustainable textile approach.
Signature 'go-kart' handling remains intact across both EV and ICE platforms.

⚠️ Weaknesses

COMPLETE ABSENCE OF DIESEL ENGINES for high-mileage drivers.
Early software bugs in the new MINI Operating System 9 (lag, freezing).
Removal of the physical iDrive rotary controller (touch or voice only now).
J01 EV is built in China, delaying its release in North America due to tariffs.
Firm ride quality, especially on 18-inch wheels or JCW trims.

🎯 Verdict

The 4th generation MINI Cooper (J01/F66) is a technological triumph that successfully bridges the gap between MINI's heritage and the electric future. For buyers specifically seeking a diesel: you must look elsewhere or buy a used Gen 3 (F56) model. MINI has definitively killed the diesel engine. However, the alternatives are excellent. If you want diesel-like running costs for urban/suburban use, the J01 Cooper SE offers fantastic EV performance and solid range. If you do heavy highway mileage (the traditional diesel use-case), the F66 Cooper C (1.5L Petrol) is surprisingly frugal, while the Cooper S remains the definitive premium hot hatch. Buy with confidence, but ensure the infotainment software is fully updated before taking delivery.