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MotorFiable

BMW B58 vs Porsche M96/M97: which engine is more reliable?

According to our risk index, the BMW B58 carries less risk than the Porsche M96/M97: 38/100 (moderate risk) versus 50/100 (high risk). The BMW B58 has 1 documented serious fault, the main one being «Failure of the oil pump with a plastic rotor housing»; the Porsche M96/M97 has 4 documented serious faults, the main one being «Failure of the intermediate shaft bearing (IMS) on the M96/M97».

Risk index

BMW B58

38

Moderate risk · 1 serious fault

Lower risk

Risk index

Porsche M96/M97

50

High risk · 4 serious faults

The index (0–100) weights the severity and frequency of the three most serious documented faults. How it is calculated

24 sourcesHow we work

Is the BMW B58 reliable?

The B58 (3.0 turbo straight-six, since 2015) is considered robust and less troublesome than the N54/N55 it replaced, and the sources do not document widespread internal failures. The known faults are on the periphery: the plastic oil filter housing, crankcase ventilation, gaskets and coolant. On units built before 2021 there are also US reports of an oil pump with a plastic housing.[1][2][3][4]

See the 6 of the BMW B58 faults

Is the Porsche M96/M97 reliable?

It depends on the version: the M96/M97 has a reputation as a fragile engine because of the IMS bearing, scored cylinders and the rear crankshaft seal, but sources disagree on how many fail and none gives a verified statistic. The most exposed are the 986 and 996 from 1999-2005; the 997.2 and 987.2 from 2009 left this behind with the MA1 engine.[5][6][7][8]

See the 9 of the Porsche M96/M97 faults

Side-by-side comparison

Comparison of BMW B58 and Porsche M96/M97
BMW B58Porsche M96/M97
Technical data
TypeEngineEngine
FuelPetrolPetrol
Displacement2,998 cm³—
TimingChainChain
Power290–441 hp204–355 hp
Productionsince 2015[9][10]1996–2008[5][6][11][12][13][14][15]
Reliability
Risk index (what is it?)38Moderate risk50High risk
Documented faults69
Of high or critical severity14
Worst severityHigh severityCritical severity
Main faults
  1. High severity: Failure of the oil pump with a plastic rotor housing
  2. Medium severity: Oil and coolant leak from the plastic oil filter housing
  3. Medium severity: Failure of the crankcase ventilation PCV valve (integrated in the valve cover)
  1. Critical severity: Failure of the intermediate shaft bearing (IMS) on the M96/M97
  2. Critical severity: Scored cylinders (bore scoring) and ‘Kolbenkipper’ on the M96/M97
  3. Critical severity: Porous blocks and cracked or displaced liners in the first M96s
Most expensive documented repairNo reliable dataNo reliable data
Which versions to buy
BuyRecommended versions
  • B58TU2 381 hp (B58B30M2, since 2022)[2][3]
None
With cautionVersions to be cautious about
  • B58 326 hp (B58B30M0, 2015-2019)[2][3][16]
  • B58 340-360 hp (B58B30M0, 2016-2019)[2][3][16]
  • B58TU 333-340 hp (B58B30M1, since 2018)[2][3]
  • B58TU 374 hp (B58B30O1, M340i, M440i and M240i, since 2019)[3]
  • 2.5 Boxster 204 hp (M96.20, 1996-1999)[17][18]
  • 2.7 and 3.2 S Boxster 220-258 hp (M96.21/.22/.23/.24, 1999-2004)[6][17]
  • 3.4 Carrera 300 hp (M96.01/.02/.04, 1997-2001)[6][19][20]
  • 3.6 Carrera 320 hp (M96.03, 2002-2005)[6][21]
  • 3.6 and 3.8 S of the 997.1, 325-355 hp (M96.05 / M97.01, 2004-2008)[7][15][22]
  • 2.7, 3.2 S and 3.4 S of the 987.1, 240-295 hp (M96.26 / M97.21 / M97.22, 2004-2008)[23][24]
AvoidVersions to avoidNoneNone

Severity of each fault: green, low; amber, medium; red, high; dark red, critical. How we rate them

Cars that each one is fitted to

BMW B58

See the 16 models with the BMW B58

Porsche M96/M97

Other comparisons

With the BMW B58

With the Porsche M96/M97

Compare other engines

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Sources

Every fact on this page links to its source. If you find an error, let us know.

  1. The 5 Most Common BMW B58 Engine ProblemsBMW Tuning · Technical documentation · published 7 February 2020 · consulted 9 October 2026
  2. BMW B58 EngineFCP Euro · Technical documentation · consulted 9 October 2026
  3. The Popular BMW B58 Inline-Six Engine Has One Big Achilles HeelThe Autopian · Motoring press · published 14 June 2024 · consulted 9 October 2026
  4. ¿En qué se diferencian los motores B58 y S58 de BMW?Diariomotor · Motoring press · published 27 April 2024 · consulted 9 October 2026 · in Spanish
  5. Porsche 996Wikipedia · Other source · consulted 2 November 2026
  6. What are the most common 996 Issues?Flat Six Innovations · Other source · published 23 November 2025 · consulted 2 November 2026
  7. Porsche 911: 5 Generationen im Gebrauchtwagen-CheckAUTO BILD · Motoring press · published 22 September 2026 · consulted 2 November 2026 · in German
  8. Differences between M96 and M97 enginesFlat Six Innovations · Other source · published 25 November 2025 · consulted 2 November 2026
  9. BMW B58Wikipedia (inglés) · Other source · consulted 9 October 2026
  10. BMW B58Wikipedia (alemán) · Other source · consulted 9 October 2026 · in German
  11. Porsche Boxster (986)Wikipedia · Other source · consulted 2 November 2026
  12. List of Porsche enginesWikipedia · Other source · consulted 2 November 2026
  13. Porsche 997Wikipedia (alemán) · Other source · consulted 2 November 2026 · in German
  14. Porsche Boxster and Cayman (987)Wikipedia · Other source · consulted 2 November 2026
  15. The Definitive Guide To Porsche 997 Engines (M96.05, M97, MA1)FCP Euro · Other source · published 16 January 2024 · consulted 2 November 2026
  16. How A Plastic Part On BMW's B58 Engine Can Turn An Oil Change Into A $3,000 RepairThe Autopian · Motoring press · published 28 March 2025 · consulted 9 October 2026
  17. 1st Generation Porsche Boxster 986 Buyer's GuideStuttcars.com · Motoring press · consulted 2 November 2026
  18. Porsche Boxster (986) 1996-2004: Stärken und Schwächenauto motor und sport · Motoring press · published 6 March 2021 · consulted 2 November 2026 · in German
  19. Porsche 996 (1997-2006) Kaufberatung: Stärken & Schwächenauto motor und sport · Motoring press · published 11 December 2018 · consulted 2 November 2026 · in German
  20. 996 Buyer's GuideRennsportKC · Other source · published 10 March 2011 · consulted 2 November 2026
  21. Porsche 911 996 Buying GuideMotorious · Motoring press · published 17 October 2018 · consulted 2 November 2026
  22. Porsche 911 Common Problems: Every Generation, Every Major IssueRenn Driver · Other source · published 4 May 2026 · consulted 2 November 2026
  23. Porsche Boxster (987) Buyer's GuideGoodwood Classic Solutions · Motoring press · published 1 March 2024 · consulted 2 November 2026
  24. Porsche Cayman and Boxster Common Problems: A Specialist Field GuideForeign Automotive · Other source · consulted 2 November 2026