B47 vs N47: Which Engine is More Reliable?
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B47 vs N47: Which Engine is More Reliable?

EngineScope

What these engines share

BMW's 2.0-litre diesel story in two chapters: the N47 (2007–2014) with its rear-mounted timing chain and the B47 (2014–present) that fixed the design. Both power the 3 Series, 5 Series, X1, and X3 in their respective eras.

B47 vs N47 at a glance

B47 N47
Brand BMW BMW
Score 80/100 35/100
Verdict BUY AVOID
Type 2.0L Turbo Diesel I4 2.0L Turbo Diesel I4
Known issues 3 2

B47 — 80/100 (BUY)

Found in: 1 Series, 2 Series, 2 Series Active Tourer, 218d, 3 Series, 320d, 320d GT, 4 Series

Key issues

  • DPF blockage — city driving — severity high, cost €1.500, onset 50.000 km
  • EGR valve / cooler carbon fouling — severity moderate, cost €800, onset 80.000 km
  • Timing chain tensioner (front-mounted) — severity moderate, cost €1.200, onset 100.000 km

Full B47 report →

N47 — 35/100 (AVOID)

Found in: 1 Series, 120d, 3 Series, 320d, 4 Series, 5 Series, 520d, Clubman

Key issues

  • Rear-mounted timing chain — catastrophic failure — severity critical, cost €6.000, onset 80.000 km
  • EGR valve failure + DPF blockage — severity high, cost €1.200, onset 60.000 km

Full N47 report →

Verdict: B47 wins by 45 points

The B47 scores 80/100 vs the N47's 35/100 — a 45-point difference. This is a significant gap. The B47 is clearly the safer choice.

Which one should you buy?

This is one of the clearest upgrade stories in BMW's lineup. The N47's rear-mounted timing chain is a known catastrophic failure point — engine-out replacement, €3.000+. The B47 moved the chain to the front, fixed the swirl flap issues, and added an AdBlue system. Buy a B47 (2014+ LCI models) every time.


Generated from EngineScope's reliability database. Reviewed by the editorial team. Methodology →