A reconditioned BMW 520d replacement engine supplied and fitted cost in the UK £2,600–£4,600. The gap between that and a bill that grows afterwards comes down to five common BMW 520d engines fitting extras: injectors, turbo, timing components, coding, and the oil pump drive.
| Route | Supplied and fitted | Cover | Notes |
| Used N47D20 engine | £2,600–£3,800 | 30–90 days | Check history carefully |
| Used B47D20 engine | £3,000–£4,000 | 30–90 days | Newer, better chain |
| Reconditioned N47D20 or B47D20 | £3,800–£4,600 | 12 months written | Uprated timing parts |
| Short engine | £3,200–£4,200 | Varies | When ancillaries are sound |
| Model | Years | Code | Watch for |
| 520d F10 | 2010–2014 | N47D20 | Rear-mounted chain, crank pulley |
| 520d F10 LCI | 2014–2017 | B47D20 | EGR cooler, chain improved |
| 520d G30 | 2017–2020 | B47D20O0 | Later revisions, fewer failures |
Before ordering a used or reconditioned BMW 520d engine, match the engine code to your REG and the BMW parts catalogue. A B47 will not go into an N47 car without major changes, and vice versa.
Before approving a BMW 520d engine replacement, ask the workshop to check each of those before the engine goes back in, and list the findings on the invoice.
On a 2012 car with 150,000 miles, a tested used BMW 520d N47D20 engine at £2,600–£3,200 fitted is a cost-effective BMW engine replacement route. On a 2018 G30 you intend to keep for five years, a reconditioned BMW 520d B47D20 engine with uprated timing parts is the better spend.
£2,600–£3,800 for a used BMW 520d engine supplied and fitted and £3,800–£4,600 for a reconditioned BMW 520d engine, supplied and fitted at independent specialist rates.
Not always, but the oil feed pipe must be replaced or cleaned. A failed BMW 520d turbo on the old engine often puts debris through the system.
Not without major changes to ancillaries and software. Match the code exactly.
On a proper BMW 520d engine supply-and-fit service it should be. Ask for it in writing, because the chain is the reason most 520d engines fail.
Three to six days for a used BMW 520d engine supplied and fitted and one to three weeks for a reconditioned unit.
For accurate BMW 520d engine replacement quotes, decode the REG and confirm the code against the BMW parts catalogue. N47D20 and B47D20 units are close relatives but not interchangeable.
During a professional BMW 520d engine fitting service, the engine comes out from above with the gearbox separated, which on a rear-drive 5 Series means the front subframe is not disturbed but the transmission tunnel work is significant.
A BMW replacement engine warranty should cover internal failure, the timing components fitted with the engine, and the labour to swap it again if required. Before choosing a BMW engine replacement specialist, ask specifically whether the oil pump drive is included.
Keep the first 500 miles gentle, check fluids daily, and re-read the codes at the end of the week. Rear-drive BMWs are sensitive to a poor installation, and the first week tells you everything.
Yes, and on a low-mileage 5 Series it can be the best route, because you keep the original engine number and gain uprated timing components. Expect two to four weeks and a tolerance report.
Old parts returned, codes printed before and after, a documented road test, and an invoice that names every component. Keep all of it with the service history.
Usually yes on N47 and B47 units. The credit helps offset the cost, but only if the core is complete and not stripped.
| Item | Typical cost |
| Used N47 or B47 engine, supplied and fitted | £2,600–£4,000 |
| Reconditioned unit, supplied and fitted | £3,800–£4,600 |
| Turbo, if required | £800–£1,500 |
| Injectors, if required | £700–£1,400 |
| Hire car per week | £200–£450 |
| Post-fit oil change | £90–£140 |
If the body, gearbox and suspension are in good order, yes. A 5 Series with a warrantied replacement BMW 520d engine and documented work still has years of life, and the alternative is losing the depreciation you have already paid.
Ignoring a cold-start rattle for months. That rattle is the cheapest repair you will ever be offered on this engine.
When comparing BMW 520d engine replacement quotes, line them up on four rows: code, warranty, inclusions and lead time. The cheaper quote usually loses once the turbo, injectors and consumables are priced in.
A tested used BMW 520d engine from a UK replacement engine specialist who knows the N47 and B47, professionally supplied and fitted within a week, with the turbo oil feed replaced at the same time. That combination avoids most repeat failures.
| Route | Upfront | Warranty cover | Expected life |
| Used N47D20 | £2,600–£3,200 | 30–90 days | Unknown |
| Used B47D20 | £3,000–£4,000 | 30–90 days | Unknown |
| Reconditioned unit | £3,800–£4,600 | 12 months written | 120,000+ miles |
| Rebuild your own | £3,000–£4,500 | Variable | 120,000+ miles |
Never ignore a cold rattle, always replace the oil feed with the engine, and buy the warranty if you are keeping the car.
Many UK BMW engine specialists accept card payments and some offer finance for a supplied and fitted BMW 520d engine, which spreads the cost of a £4,000 engine over a year. Ask before you assume you have to find the full amount up front.
Need a BMW 520d engine quote? Compare a fully itemized price for a used or reconditioned BMW 520d engine supplied and fitted in the UK, with the engine code, labour, timing components, diagnostics and written warranty clearly confirmed before work begins.
Read More About BMW 520d Engines
