Comparison

BMW N47 vs B47: Which Diesel Engine Is More Reliable?

N47 vs B47 direct comparison. B47 resolves the timing chain issue that made N47 ownership expensive. Is the B47 genuinely better? Fault rates, costs and longevity compared.

📅 Updated Jun 2026 👁 1 views
Risk:
5/10

Comparison

CategoryN47B47Winner
Timing chain position Rear — gearbox removal usually required Front — conventional access B47 by large margin
Chain replacement cost £1,500-3,200 £600-1,200 (if needed — much rarer) B47
EGR reliability Above average fouling rate Improved management — lower fault rate B47
Cooling system Plastic components prone to cracking Revised specification — lower failure rate B47
Power output 115-184 bhp depending on tune 150-190 bhp in most applications B47
Fuel economy 50-58 mpg combined (official) 54-62 mpg combined (official) B47
Long-term reliability score 5 8 B47

Reliability Verdict

B47 is unambiguously the better engine. The timing chain relocation alone eliminates the most expensive and stressful repair in the N47 ownership experience. EGR and cooling improvements are secondary benefits.

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Important Notice: This page is based on owner reports, community discussions and MyCarFault case data. It is not an official manufacturer defect notice. Information about costs and reliability reflects community-reported experiences and may not apply to your specific vehicle. Always confirm diagnosis with a qualified mechanic before making repair or purchase decisions. MyCarFault makes no warranty as to the accuracy or completeness of any information on this page.
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