5 Seriesbuyer's guide

The F10 5 Series is one of the best executive saloons of its era and one of the fastest depreciating — which means the used market is full of examples that someone else stopped maintaining. Timing belt/chain or oil-service risk is the fault with the biggest bill attached: neglected N20 or N47 timing systems can cost $500–$4,500, and that figure goes higher with internal engine damage. Automatic/DSG/clutch judder on the ZF 8HP is right behind it at $900–$5,500 if fluid service history is absent.

This guide covers ten known issues: Timing belt/chain or oil-service risk, Automatic/DSG/clutch judder, Coolant leak or water pump fault, Infotainment/software electrical faults, Suspension knocks and tyre wear, Brake corrosion or EPB fault, Oil leak or PCV fault, Panoramic roof or boot water leak, ADAS/radar calibration fault, and Recall/campaign status. Each fault has a field check and a real repair-cost range.

A one- or two-owner F10 with a main-dealer service file, no oil weeps under the bonnet and a clean scan is genuinely good value. A four-owner car with a patchy history, fresh code clearing and a damp boot floor is a money pit. This guide gives you the checks to know the difference on the driveway.