BMW X4 M40i Engine Replacement — Compare Prices & Get Quotes
Get quotes today from trusted UK BMW X4 M40i specialists. Compare reconditioned, rebuilt and used 3.0-litre turbocharged straight-six engines - N55 and B58 variants across the F26 and G02 generations - supply & fit available nationwide.
The X4 M40i THROUGH TIME - Era Map
Four generations. Four eras. One guide to reliability, costs and what really matters.
Era Note
3.0L single-turbo straight-six - 360 hp, 465 Nm; proven N55; HPFP and oil leaks are the main watch items
Why use this era map?
This table is the single source every other section on this page matches - Sections 2, 4 and 6 reference it rather than restating conflicting figures.
BMW X4 M40i Engine Replacement Costs
Figures above reflect current X4 M40i replacement costs. The B58 variant typically sits at the higher end of the range. See the Era Map above for generation-specific pricing.
Labour estimate: Fitting an X4 M40i engine typically takes 14–18 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer).
Weighing Your Options?
Compare Specialist Quotes When You're Ready
20+ vetted BMW specialists, every X4 M40i variant covered, with a 12-month warranty as standard.
See X4 M40i Engine Options
X4 M40i - Repair, Buy, or Replace?
Every 320d has a story. Make the right call with clear data, real-world costs, and honest guidance from UK specialists.
Can It Be Repaired?
Buying This X4 M40i? Check These First
Buy If
- G02 (2018+) with the B58 engine (modular design, improved reliability)
- Post-2019 B58TU1 with revised timing chain and fuel system
- Documented service history with regular oil changes (critical for chain and VANOS longevity)
- No oil leaks around the valve cover or oil filter housing
- Water pump replaced as preventative at 50k+ miles
Avoid If
- Oil leaks around the oil filter housing (belt damage risk on B58)
- Overheating history or unexplained coolant loss - cooling system may be compromised
- No service history - both N55 and B58 are sensitive to oil quality
- VANOS system failure symptoms - loss of power, rough idle
Closing Verdict
The X4 M40i is BMW's M Performance coupe-SUV - a 3.0-litre turbocharged straight-six powerhouse that delivers 360–387 hp and effortless torque. The F26 (2015–2018) uses the N55 - a proven single-turbo engine with a strong reliability record. The G02 (2018+) uses the B58 - part of BMW's modular engine family, widely regarded as one of BMW's most reliable modern engines. The B58 has gained a solid reputation for performance, smooth operation and tunability. Common issues across both engines include oil leaks (valve cover gasket, oil filter housing), VANOS solenoid failure, water pump failure, and HPFP issues. With typical X4 M40i values ranging from £20,000 (F26) to £45,000+ (G02), an engine replacement is a major financial commitment - but the B58 is generally reliable when properly maintained. A post-2019 B58TU1 with documented history is the safest choice.
Don't Guess. Compare.
Get real quotes from vetted UK specialists and make the right call for your 320d.
→ Compare X4 M40i engine prices before you buy
Buying Checklist
Before you buy a used BMW X4 M40i (or before you commit to an engine replacement), check these:
Cold Start
Listen for smooth idle; any rattling or rough running may indicate VANOS or timing issues - see the map above
Service History
Including which engine era (N55B30T0 or B58B30M0/O1) and oil-change discipline
Oil Leaks
Check around valve cover and oil filter housing for leaks
Coolant Level
Check reservoir when cold; any low or loss may indicate water pump or cooling system issues
VANOS Health
Test acceleration; any loss of power or sluggish response may indicate VANOS solenoid wear
Turbo Health
Test acceleration; any lag, whistling, or hesitation?
Engine Warning Light
Have codes read; unresolved issues may indicate HPFP, VANOS or sensor problems
MOT History
Check for emissions-related failures
Buy smart. Drive with confidence.
A few checks today can save thousands tomorrow. Use this checklist to avoid the most common 320d pitfalls.
BMW 320d Engine Codes
This table's rows match Section 1B's Era Map exactly.
N55B30T0
Technical Specs
N55B30T0 - F26 generation→ Compare X4 M40i engine prices for your X4
Get quotes from trusted UK specialists in minutes.
Market Intelligence
Most Common Failure
Oil leaks (valve cover gasket, oil filter housing)
the most frequent X4 M40i enquiry
Average Enquiry Mileage
50,000
–70,000 miles
[PATTERN DATA]
Average Replacement Cost
£6,500
–£8,000 reconditioned, supply only
[PLACEHOLDER]
Most Requested Engine Code
B58B30O1 / B58B30M0
[PATTERN DATA]
Peak Enquiry Season
Winter
cold starts expose oil leaks and VANOS issues
[PATTERN DATA]
Regional Demand
PATTERN DATA
Regional Demand Breakdown
BMW 320d - Frequently Asked Questions
All prices are indicative UK market ranges based on historical quote data from our network of engine specialists. Actual costs vary by variant, engine condition, damage severity and workshop location. Use our free comparison tool to get tailored quotes. Every engine supplied through EnginesMarket carries a minimum 12-month unlimited-mileage warranty - always confirm terms with your chosen supplier.
Why UK BMW X4 M40i Owners Trust BMWEngines.uk
Trusted X4 M40i Engine Suppliers
every garage and engine rebuilder in our network is vetted, rated and reviewed by real X4 M40i owners, as part of the Engine Finders network, across every engine era - N55 and B58 - covering the F26 and G02 generations.
Compare X4 M40i Engine Replacement Companies
see prices, warranty terms and supply & fit options side-by-side before you commit. We cover the 3.0-litre turbocharged straight-six specifically, with specialists who understand the N55 and B58's oil leak vulnerabilities, VANOS system requirements, and cooling system demands.
UK Engine Replacement Services for X4 M40i
supply-only or full supply & fit available nationwide, covering every generation of this badge since 2015, with a 12-month warranty as standard across our network.
Find the best BMW X4 M40i engine replacement UK drivers rely on. Compare prices from trusted specialists on EnginesMarket today and get your X4 M40i back on the road with confidence.
Explore BMW X4 M40i Engine Quotes100% Free
No hidden fees
No Obligation
Get quotes with zero pressure
UK Specialists
20+ vetted experts
12-Month Warranty
As standard
Nationwide Delivery
Supply & fit available
100% Free
No hidden fees
No Obligation
Get quotes with zero pressure
UK Specialists
20+ vetted experts
12-Month Warranty
As standard
Nationwide Delivery
Supply & fit available