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S55 Common Problems & Reliability
How robust the F80's twin-turbo S55 really is — the crank hub and rod bearings, the smaller wear items, and how to buy and own one with confidence.
Read the guide →The Crank Hub Problem
The S55's signature concern explained — what the crank hub is, why it slips, the warning signs and the pinning fix.
Read guide →Rod Bearings Explained
The M-engine rod-bearing question — the wear, the preventive-replacement debate, and what it means for buyers.
Read guide →Buying
F80 M3 Buyer's Guide
Crank hub and rod-bearing history, track abuse, tune records, DCT vs manual, and a full inspection.
Read guide →DCT vs 6-Speed Manual
The two gearboxes compared — which to buy, and how each drives.
Read guide →DIY & Maintenance
Oil Change (S55)
The routine service done right, with the correct M-spec oil and capacity.
Read guide →Spark Plugs & Coils
The S55 ignition refresh, plus the colder plug a tuned car wants.
Read guide →Brake Pads & Rotors
Front and rear pads and rotors, with the electronic parking brake in service mode — plus the carbon-ceramic caution.
Read guide →