Most 2018 S‑Max diesels are 2.0-litre EcoBlue units with a manual gearbox; they give good real-world mpg on A‑roads and motorways but use a DPF and EGR system (and some Euro6 diesels use AdBlue dosing). Manual clutch wear is the main transmission concern on an 8‑year-old example, and many S‑Max buyers choose them for the optional 7-seat layout so check how the third row stows and if the latches work smoothly.

• DPF / EGR behaviour and soot: look for frequent DPF regen events, check for warning lights and excessive smoke after a cold start (short-trip cars are most at risk).
• AdBlue system faults (if fitted): check filler cap, tank level sensor and for any dosing-related warning messages on the dash.
• Clutch condition and gear selection: test for slip under load, uneven bite point or noisy synchros when changing gears.
• Third-row seats and latches: operate folding mechanism, check seatbelts and that seats lock securely and fold/raise without catching.
• Rear suspension bushes and ride height: check for creaks, uneven ride or sagging rear (common if the car has been heavily loaded frequently).