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BMW B58 vs M271: which engine is more reliable?

According to our risk index, the BMW B58 carries less risk than the M271: 38/100 (moderate risk) versus 59/100 (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 M271 has 1 documented serious fault, the main one being «Timing chain stretch and wear of the camshaft sprockets».

Risk index

BMW B58

38

Moderate risk · 1 serious fault

Lower risk

Risk index

M271

59

High risk · 1 serious fault

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

10 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 M271 reliable?

The M271 is the four-cylinder petrol engine Mercedes-Benz fitted from 2002 to 2015, first with a mechanical supercharger (Kompressor) and, from 2009, with a turbo in the EVO revision. It has one well-documented weak point across the range: the timing chain and the camshaft sprockets can wear prematurely, a problem a specialist source describes as persistent even after the EVO redesign.[5][6][7]

See the 4 of the M271 faults

Side-by-side comparison

Comparison of BMW B58 and M271
BMW B58M271
Technical data
TypeEngineEngine
FuelPetrolPetrol
Displacement2,998 cm³1,796 cm³
TimingChainChain
Power290–441 hp122–204 hp
Productionsince 2015[8][9]2002–2015[6][7]
Reliability
Risk index (what is it?)38Moderate risk59High risk
Documented faults64
Of high or critical severity11
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: Timing chain stretch and wear of the camshaft sprockets
  2. Medium severity: Oil leaking from the camshaft adjuster solenoids into the wiring
  3. Medium severity: Crankcase ventilation hose under the supercharger: it cracks and lets in false air
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][10]
  • B58 340-360 hp (B58B30M0, 2016-2019)[2][3][10]
  • B58TU 333-340 hp (B58B30M1, since 2018)[2][3]
  • B58TU 374 hp (B58B30O1, M340i, M440i and M240i, since 2019)[3]
  • M271 Kompressor 1.6/1.8 (KE16/KE18)[5]
  • M271 EVO 1.8 turbo CGI (DE18 LA)[5]
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 15 models with the BMW B58

M271

See the 7 models with the M271

Other comparisons

With the BMW B58

With the M271

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. Mercedes M271: Typische Probleme und HaltbarkeitGebrauchtwagenberater · Motoring press · consulted 27 September 2026 · in German
  6. Mercedes-Benz M271 engineWikipedia · Other source · consulted 27 September 2026
  7. Mercedes-Benz M 271Wikipedia (alemán) · Other source · consulted 27 September 2026 · in German
  8. BMW B58Wikipedia (inglés) · Other source · consulted 9 October 2026
  9. BMW B58Wikipedia (alemán) · Other source · consulted 9 October 2026 · in German
  10. 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