The high-revving naturally aspirated V8 built for the E90/E92 M3 — an engineering highlight of its era, with one specific, well-documented wear issue that defines how any purchase decision should be made.
This is a genuinely special engine — an 8,400rpm naturally aspirated V8 derived from BMW's Formula 1 program of the era — and that motorsport-adjacent design is exactly why rod bearing wear became such a well-known concern. The bearings were specified with tighter tolerances than a typical road engine, and a meaningful number failed prematurely, sometimes with limited warning. Addressed proactively, it's not disqualifying; ignored, it's the one issue that can end this engine's life suddenly.
Not a guarantee, but a pattern seen consistently across owner forums and independent-garage reporting.
Rod bearing wear has been reported across a wide mileage range, including relatively low-mileage examples — it is not purely a high-mileage concern.
The range where proactive rod bearing inspection or replacement is most commonly recommended by specialists if not already done.
Examples with documented, proactive bearing replacement commonly continue reliably well beyond this point.
This is the single most important step on any S65: have a specialist perform a rod bearing inspection (often via a borescope or oil analysis) before committing, regardless of what the seller claims about mileage or history.
Listen carefully for a knocking sound, particularly on a cold start, and treat any unexplained engine noise as disqualifying until assessed.
Ask about oil change frequency specifically — this engine is less forgiving of extended intervals than a typical road-going BMW six.
Model-specific pages, with notes on how it behaves in that particular car.