BMW X5 30si Engine ReplacementCompare Prices & Get Quotes

A full BMW X5 30si engine replacement typically costs £2,200-£4,200 supply-only for a rebuilt N52B30 unit, or £3,500-£5,500 fitted by a specialist. Used engines start from £800, while reconditioned units typically cost £1,600-£3,000.

• Prices vary by exact N52 variant (N52B30A / N52B30AF / N52B30BF)
• Professional fitting adds £800-£1,200 to any engine purchase
• Rebuilt units include upgraded valvetronic and timing components
• 12-month unlimited-mileage warranty on all rebuilt engines

The N52B30 family has three well-documented failure points: valvetronic motor failure (rough idle, reduced power), electric water pump failure (sudden overheating), and oil filter housing gasket leaks (burning oil smell). All three typically appear between 60,000-120,000 miles.

• Valvetronic motor replacement at specialist: £500-£900
• Water pump replacement at specialist: £450-£750
• Oil filter housing gasket at specialist: £300-£500
• Catch issues early to avoid full engine replacement

The N52 is generally well-regarded for reliability - it's BMW's final naturally aspirated straight-six and is smoother and more characterful than the turbocharged engines that followed. With proper maintenance, N52 engines regularly exceed 150,000-200,000 miles.

• Annual oil changes (not BMW's extended intervals) are critical
• Valvetronic motor and water pump are the main wear items
• N52 engines are less problematic than N47/N57 diesel units
• Many specialists report N52s reaching 200,000+ miles with preventative maintenance

For a 2006-2008 X5 30si worth £2,850-£8,425, a £2,200-£4,200 rebuilt N52 engine can make financial sense if the body, gearbox, and interior are in good condition. The decision depends on the individual car's condition and your ownership horizon.

• Compare replacement cost against vehicle value (typically 40-70% on lower-value examples)
• If body and gearbox are sound, a rebuilt engine can add years of life
• Used engine (£800-£1,600) is the budget option for short-term ownership
• Rebuilt engine (£2,200-£4,200) offers warranty and peace of mind

The 30si (2006-2008) uses the naturally aspirated N52B30 straight-six petrol engine producing 272hp. The xDrive35i (2009 onwards) replaced it with the turbocharged N55B30 producing 306hp - a significant power increase and different driving character.

• 30si: naturally aspirated, 272hp, smoother power delivery, simpler engine
• 35i: turbocharged, 306hp, more torque, more complex (charge pipe, turbo issues)
• 30si is the choice for buyers seeking BMW's last naturally aspirated six
• Engine codes are not interchangeable - always match the correct code

Engine swaps to a different size or fuel type are technically complex and rarely cost-effective on the E70 X5. Stick to like-for-like replacement using the correct N52 engine code (N52B30A, N52B30AF, or N52B30BF) for your X5 30si.

• ECU, wiring loom, fuel system, and exhaust all differ between petrol and diesel
• Transmission ratios differ between engine variants
• Insurance must be notified of any non-standard engine swap
• Specialist marketplace only recommends like-for-like code-matching