N53 vs M50/M52 — Reliability Comparison

Specifications

N53

M50/M52

Brand

BMW

Verdict

CAUTION

BEST

Reliability

52

86

Years

2006--2013

1990--2001

Displacement

2996 cc

2494 cc

Layout

I6

Type

Petrol Na

Power

190--272 hp

150--193 hp

Known Issues

7

5

Total Risk Cost

€620--€4,800

€430--€2,200

Character

N53

"Direct-injection version of the N52 for Europe only (it needs low-sulphur fuel). It shares the N54 fault list minus the turbos: piezo injectors, the high-pressure fuel pump and the NOx sensor/catalyst are the expensive items, plus oil leaks with age. Buy only with records showing late-index injectors and the pump already done."

M50/M52

"Smooth, linear inline-six with bulletproof internals — 300,000 km is routine. Budget a full cooling-system refresh (plastic tank, impeller, thermostat housing) and expect VANOS seals and the oil separator to need doing. Only trap: European M52 built 1995 to early 1998 had Nikasil bores that sulphur fuel destroyed; ask for a leak-down test or proof of a replacement block. M50 and M52TU are not affected."

Issues Comparison

N53 7

▲ HIGH

High-pressure fuel pump failure N/A--N/A 24,000 km--161,000 km

▲ HIGH

Piezo injector failure — misfire and rough idle €220--€1,800 N/A--N/A

▲ HIGH

NOx sensor and NOx storage catalyst failure €400--€3,000 N/A--N/A

● MODERATE

Oil leaks and consumption — valve cover, breather, oil filter housing N/A--N/A N/A--N/A

○ MINOR

VANOS solenoid valve failure N/A--N/A N/A--N/A

○ MINOR

Carbon deposits on intake valves and injectors (direct injection) N/A--N/A N/A--N/A

○ MINOR

Ignition coil failure (2007-2008 service campaign) N/A--N/A N/A--N/A

M50/M52 5

◆ CRITICAL

Nikasil cylinder-bore wear (M52 built 1995 to March 1998, non-US) N/A--N/A 48,000 km--N/A

● MODERATE

Crankcase ventilation (CCV / oil separator) clogs — oil consumption, rough idle €100--N/A 130,000 km--195,000 km

● MODERATE

Cooling system plastics (tank, housing, impeller) €150--€1,700 97,000 km--240,000 km

○ MINOR

VANOS oil seal wear (M50TU from 1992, M52, M52TU) €80--€200 120,000 km--200,000 km

○ MINOR

Valve cover / oil pan gasket leaks €100--€300 150,000 km--∞

Models

N53 5

6 Series E63 2007--2010 5 Series E60 2007--2010 5 Series E60 2007--2010 3 Series E90 2007--2011 3 Series E90 2007--2012

M50/M52 12

3 Series E36 1990--1994 3 Series E36 1990--1995 5 Series E39 1996--2000 3 Series E36 1994--1999 3 Series E46 1998--2001 5 Series E39 1996--2000 3 Series E36 1995--1999 3 Series E46 1998--2000 5 Series E39 1996--2000 3 Series E36 1995--1999 Z3 E36/7 1997--2000 3 Series E46 1998--2000