Most 2023 5 Series diesels you’ll see in Ireland are Euro6 units (e.g. 520d/530d range) paired with BMW’s automatic ZF 8-speed box — very efficient on long runs but they use AdBlue and have a DPF. The automatic gearbox is generally smooth but benefits from documented software/gearbox fluid attention; diesel-specific items to watch for are DPF clogging and AdBlue system faults, especially if the car has mostly short urban trips. As a premium BMW, servicing and parts are more expensive than mainstream brands but parts are widely available locally.

• DPF behaviour — ask if there are recent successful regenerations and check for soot smell, frequent limp modes or long-term low-speed urban use which clogs the filter
• AdBlue system and filler cap — confirm no warning lights, check top-up history and look for injector/line leaks
• Automatic gearbox shifts — test for smooth, crisp up/down shifts and for any hesitation or knock on cold starts; ask about gearbox oil/service history (ZF 8-speed attention)
• Turbo response and smoke under hard acceleration — listen for unusual turbo whine, rattles or visible exhaust smoke
• Suspension and brakes — check for uneven tyre wear, knocking from bushings and correct ride height (adaptive/air suspension optional on higher specs can be costly to repair)