BMW N47 Timing Chain: The Diesel Failure Every Used Buyer Should Check For

If you're shopping for a used BMW diesel from roughly 2007 to 2015, there's one check that matters more than the service book, the paint, or the tyres: the timing chain.

The N47 2.0-litre diesel is one of the most widely fitted engines BMW ever built — and it carries a design decision that has cost owners across Europe a great deal of money. Get this check right and a well-kept N47 car is a genuinely good buy. Get it wrong and you can be facing a four-figure bill within months.

Why this engine is different

Most engines put the timing chain at the front, where it's reachable. The N47 puts it at the back of the engine, behind the flywheel — against the gearbox.

That single packaging choice is the whole story. The chain and its plastic guides wear like any other. But when they need attention on an N47, the workshop has to separate the gearbox from the engine to get to them. What would be a moderate job on most cars becomes a very expensive one — and, worse, it means a failing chain can't simply be inspected on a ramp.

If the chain skips or snaps, the pistons and valves collide. At that point you are looking at a rebuilt or replacement engine, not a repair.

Which cars are affected

The N47 was fitted across an enormous slice of the range from 2007 to around 2015:

• 1 Series — 116d, 118d, 120d (E87/E81, F20)
• 3 Series — 316d, 318d, 320d (E90/E91, F30)
• 5 Series — 520d (E60, F10)
• X1 — sDrive18d, sDrive20d (E84)
• X3 — sDrive18d, xDrive20d (F25)
• Various Touring, Coupé, Convertible and GT variants of the above

In short: if it's a BMW with a 2.0 diesel badge from that era, assume it's an N47 until proven otherwise.

The important nuance: not all N47s are equal

This is where most advice online goes wrong by treating every N47 as a write-off. BMW revised the chain, guides and related components in stages:

• 2007 – 2009 cars are the highest risk. Original chain and guide design, rear-mounted, and now old enough that most have entered the danger zone.
• A 2009 revision brought redesigned components (available retrofitted to older engines under a "quality enhancement" programme in some markets), reducing — not eliminating — failure rates.
• A further 2011 revision improved things again. Later cars are meaningfully better, but "improved" is not "immune," and failures on later builds are still reported.

The practical rule: the older the car, the higher the risk — and every N47 deserves the check below regardless of year.

The danger zone: mileage

Most failures cluster after roughly 130,000–190,000 km (80,000–120,000 miles), though poor maintenance can bring it forward dramatically. Two factors accelerate it hard:

• Extended or missed oil changes. The chain relies on clean oil and oil pressure to keep its tensioner working. Long-life servicing intervals are the enemy here — annual or 15,000 km oil changes are cheap insurance.
• Short journeys. A diesel that never gets fully warm suffers on oil quality (and on its DPF at the same time).

How to check it in 30 seconds at the viewing

This is the single most valuable thing in this article, and it costs nothing:

1. Insist the car is stone cold when you arrive. Not "warmed up ready for you" — cold. A seller who has pre-warmed the engine may simply be being helpful, but it also happens to hide the exact symptom you're listening for. If they won't let you start it cold, treat that as a red flag.
2. Stand at the back of the engine bay (near the bulkhead, not the front) and start it.
3. Listen for the first 1–3 seconds. A healthy N47 fires and settles into normal diesel clatter. A worn chain produces a distinctly harsher, metallic rattle from the rear of the engine — commonly described as a chainsaw or a bag of spanners — which then fades as oil pressure builds and tensions the chain.

That fading-rattle-from-the-back is the classic tell. Other supporting signs: rough idle, difficulty restarting shortly after a stop, and any engine-management light.

If you hear it, walk away. Not "negotiate" — walk away. Once the noise is audible, the repair is imminent and expensive.

What it costs

Because of the gearbox-out access, this is a labour job more than a parts job:

• Preventive chain, tensioner and guide replacement: typically €1,800–€3,000 at an independent BMW specialist, with the workshop time running to 12–18+ hours (more on engine-out jobs). Main-dealer pricing goes higher.
• After a failure: a replacement or rebuilt engine, commonly €4,000–€7,000+ fitted. This is why the car is often written off economically instead.

Note the asymmetry: the preventive job is expensive, but it's a fraction of the failure. On a high-mileage N47 with no chain history, budget for it as a probable cost rather than hoping.

Should you buy an N47 car at all?

Yes — with conditions. These are otherwise good cars: economical, torquey, comfortable, and now very cheap relative to what they were. The engine's other systems (turbo, EGR, DPF, swirl flaps on some variants) are ordinary diesel maintenance items, not disasters.

Buy one if:

• It's a later build (2011+) where possible, and
• It has documented, regular oil changes — ideally more frequent than BMW's long-life intervals, and
• It's silent from the rear on a cold start, and
• Either the chain has already been done with paperwork to prove it (a genuine value-add — that car is arguably safer than an untouched one), or you've priced the job into your offer.

Avoid one if: it rattles, the service history is patchy or absent, or the price assumes nothing will ever go wrong.

The wider point

The N47 is the perfect illustration of why buying on badge and mileage alone fails. Two identical-looking 320d saloons on the same forecourt — same year, same mileage, same price — can be separated by a €3,000 liability that comes down to which engine build it has and how it was serviced.

That's precisely what our data is built for: run the exact car through the AutoFindr analyzer — make, model, year, mileage — for its composite reliability score and the documented failure modes for that engine at that mileage, with repair-cost bands. Use the maintenance cost estimator to budget the years ahead honestly, and pull a VIN history check so you know the car's past as well as its engineering (AutoFindr readers get 20% off carVertical with code AUTOFINDR).

And if you want the petrol side of BMW's modern range, we've covered the B58 and S58 in the same detail — both far happier stories than this one.

Bottom line

• The risk: rear-mounted timing chain; failure destroys the engine.
• Affected: most BMW 2.0 diesels, 2007–2015; oldest cars are worst, 2011+ improved.
• The danger zone: ~130,000–190,000 km, sooner with neglected oil changes.
• The check: cold start, listen at the rear, 1–3 seconds. Rattle = walk away.
• The cost: €1,800–€3,000 preventive; €4,000–€7,000+ after failure.

Thirty seconds of listening, in exchange for the biggest single risk on the car. There aren't many checks with that return.