BMW 520d (2010-2023) Used Buyer's Guide
The 520d is the diesel that built the modern 5 Series in Estonia: efficient, refined and genuinely comfortable over long distances. It spans two generations here, the F10 (2010-2017) and the G30 (2017-2023), and the engine matters as much as the body, because the earlier N47 and the later B47 are not equally robust. A well-kept G30 with the B47 is a different ownership proposition from an early F10 with a stretched timing chain. This guide separates the two so you know which faults actually apply to the car in front of you.
Strengths
- Real-world fuel economy is genuinely strong for a large saloon. Owners report roughly 5.0-5.5 L/100km on a motorway run, which keeps running costs sensible even on a heavy car.
- The ZF 8-speed automatic fitted to almost every 520d is one of the best gearboxes in any car. Shifts are smooth and well-timed, and it holds up well when the oil is actually serviced.
- It is a quiet, long-legged motorway cruiser. The diesel settles down once warm, and the chassis soaks up Estonian road surfaces better than most rivals.
- The later B47 engine (broadly 2014 onward, standard across the G30) is a clear step up in durability over the N47, thanks to a redesigned and strengthened timing chain that is far less prone to stretch, though it stays at the rear of the engine, so the rare chain job is still engine-out.
- Parts and independent specialist support are widespread. The 5 Series is common enough in the Baltics that most workshops know it, which keeps labour competitive versus a rarer executive car.
- Build quality and the interior age well. Switchgear, seats and trim generally hold together, and a clean, documented example still feels premium years later.
Weak points and common problems
- Common on early N47s, less so on the F10 (medium confidence, N47 diesel, F10 roughly 2010-2013): timing chain stretch and wear. The worst failures were concentrated on pre-2011 N47s, and most F10 cars got a revised chain that fails far less often, but it is still the one fault that can write off the engine. The N47 runs its chain at the back of the engine, and a stretched chain rattles on cold start from the bulkhead side. If it jumps or snaps the engine can be badly damaged, and because the chain is at the rear the job is labour-heavy. Budget EUR 1500-2500 for a preventative chain kit; a failed engine is far more. Treat any rattle on a cold N47 as a stop-and-inspect.
- Common (high confidence, recall, N47/B47/N57 diesels): the EGR cooler. BMW issued a genuine safety recall because the cooler can leak internally, letting coolant mix with exhaust soot, which in rare cases led to smouldering and fire risk. Check that the recall work was carried out. If a car still shows mysterious coolant loss or an EGR fault, budget EUR 400-800 for the cooler and related parts.
- Occasional (medium confidence, both generations): cooling system plastic parts. The electric water pump, thermostat and plastic housings are wear items and tend to fail with age rather than mileage, often flagging an overheat or coolant warning. A water pump and thermostat together is typically EUR 500-900 fitted at an independent.
- Occasional (medium confidence, cars with optional rear self-levelling or air suspension): air spring and compressor leaks. A car that sits low at the back overnight or pumps the compressor constantly usually has a leaking air spring or a stuck valve. A single rear air spring tends to run EUR 300-600 per side; a compressor is more.
- Occasional (medium confidence, both generations, more reported on G30 from 60 000 km): front suspension wear. Worn control arm bushings and links cause clunks over bumps and uneven tyre wear. This is the single most common repair area on the newer cars. Front arms and bushings typically cost EUR 400-800 per axle depending on what is replaced.
- Occasional (medium confidence, all diesels, worse on short-trip cars): DPF and AdBlue (SCR) issues. A 520d used only for short city hops can clog its diesel particulate filter and throw power-loss or warning lights. AdBlue dosing-injector or sensor faults are owner-reported on Euro 6 cars and tend to run EUR 300-600. Regular longer drives are the cheapest prevention.
- Occasional (medium confidence, both generations): oil leaks from the valve-cover gasket, oil-filter-housing gasket and turbo oil lines. Symptoms are an oil smell or weeping seen on the underside. Individually these are not dramatic, roughly EUR 200-500 a gasket, but several at once add up.
- Occasional (medium confidence, ZF 8HP gearbox, higher mileage): the gearbox is reliable but not truly sealed for life. Neglected fluid, or a leaking mechatronic or output-shaft seal, can show as harsh or hesitant shifts. An oil and filter service is roughly EUR 250-450 and is cheap insurance; ignoring it is the expensive path.
- Occasional (medium confidence, G30, cars left standing): battery drain from modules not entering sleep. A car that sits for days and then will not start, or shows random electrical warnings, often has a module staying awake. Diagnosis time plus a battery can run EUR 200-450.
Maintenance by mileage
- Oil and filter on the recommended interval, and shorter if the car does mostly short trips.
- Brake fluid change and a full brake inspection.
- First proper inspection of front suspension bushings and links for early clunks.
- Confirm the EGR cooler recall has been completed on diesel cars.
- ZF 8-speed gearbox oil and filter service, even though it is marketed as lifetime fill.
- Cooling system check: water pump, thermostat and hoses for weeping or play.
- Inspect the DPF and AdBlue system health, especially on city-driven cars.
- Replace worn front control arm bushings if clunks have appeared.
- On an N47 (early F10), assess the timing chain seriously and budget a preventative kit if there is any rattle.
- Refresh the cooling system proactively if it has not been touched.
- Check the air or self-levelling suspension if fitted for slow leaks.
- Replace valve-cover and oil-filter-housing gaskets if leaks are present.
- Full underbody and suspension overhaul: arms, bushings, links and drop links as needed.
- Second ZF gearbox service if the car is kept long term.
- DPF condition assessment; plan for cleaning or replacement if regeneration struggles.
- Auxiliary and turbo systems check for oil leaks and worn lines.
Suggested checks. Real intervals depend on the engine, equipment and how the car was used.
Is it worth buying?
A 520d can be an excellent long-distance car in Estonia, but the badge hides two very different cars. An early F10 with the N47 needs a clean service history and zero cold-start rattle, because the rear timing chain is the one fault that can write off the engine. A later F10 or, better, a G30 with the B47 is a much safer bet, provided the EGR cooler recall is done and the suspension and cooling system have been maintained. Buy on documented history rather than mileage alone, and have any candidate inspected by someone who knows BMW diesels. Done right, it is a genuinely rewarding car to own for years.
Frequently asked questions
Is the BMW 520d reliable?
It can be, but it depends heavily on engine and history. The later B47 diesel (broadly 2014 onward, standard on the G30) is notably more durable than the earlier N47. A documented service record, completed EGR recall and evidence of gearbox and cooling maintenance matter more than the year on the plate.
What is the difference between the F10 and G30 520d?
The F10 (2010-2017) is the older generation and early cars use the N47 diesel with its rear timing chain. The G30 (2017-2023) is newer, uses the more robust B47 diesel, and brings better technology and refinement. As a used buy the G30 generally carries lower mechanical risk.
Which engine is in the 520d, N47 or B47?
Early F10 cars use the N47 four-cylinder diesel; later F10 and all G30 cars use the B47. The key practical difference is the timing chain: both run it at the rear of the engine, but the N47 chain is prone to stretching while the B47 uses a redesigned, strengthened chain that is far more reliable. A chain job stays labour-heavy (engine-out) on either, but the B47 rarely needs one.
Was there a recall on the BMW 520d diesel?
Yes. BMW issued a genuine safety recall covering the EGR cooler on N47, B47 and N57 diesel engines, because the cooler could leak internally and in rare cases create a fire risk. Always confirm the recall work was carried out on any diesel 5 Series you consider.
How much does the timing chain cost to fix on an N47 520d?
A preventative timing chain kit on an N47 typically runs around EUR 1500-2500 at an independent specialist because the chain sits at the rear of the engine and is labour-intensive. If the chain actually fails and damages the engine, the bill is far higher, which is why a cold-start rattle is a serious warning.
Does the ZF 8-speed gearbox need servicing?
Yes, despite being marketed as a lifetime fill. An oil and filter service roughly every 100 000 km, around EUR 250-450, helps the gearbox last and avoids harsh or hesitant shifts later. It is cheap insurance against a very expensive repair.
Is the air suspension a problem on the 520d?
Only some cars have rear self-levelling or air suspension, and when fitted it can develop slow leaks with age. A car that drops at the back overnight or runs its compressor constantly should be checked. A single rear air spring tends to cost EUR 300-600 per side, so factor it in if the car has it.