F26
2014–2018
• N20, N55 - based on F25 X3 platform
X4 Engines –
The Complete UK Guide
Every BMW X4 engine across two generations - from the N20 four-cylinder and N55 six-cylinder of the F26 to the B48, B58 and S58 of the G02. Real UK replacement costs, known failure patterns, and honest ownership economics for BMW's stylish coupé-SUV. Backed by real UK X4 engine enquiries in 2025 [BMW-VERIFIED].
Explore X4 Engines- X4 Enquiries (2025)[BMW-VERIFIED]
- 2Generations Covered
- 10+Engine Codes
- Part ofEngine Finders
BMW X4 -
The Ownership Verdict
One-line verdict:
The X4 is BMW's style-led SUV - the X3's sportier sibling with a coupé roofline. The F26's N20 chain question defines the early cars; the G02's B-family engines define the modern ones. Buy on the generation line, not the badge.
Verdict MetricOur Call
Overall Ownership Rating
(3.8/5)
Replacement Economics
The X4 rule - style over substance: an N20 recon at £2,800–£4,800 against a £6,000–£10,000 F26 is 28–80% - ⚠️ watch. A B48/B58 recon at £3,000–£6,000 against a £15,000–£25,000 G02 is 12–40% - ✅ safe. Generation decides everything.
Reliability
- the B48/B58 are the modern gold standard; the N55 is robust; the N20 carries the chain-tensioner caveat
Most Reliable Engine
B58B30 (G02 M40i) and B48B20 - the modular B-family engines are the modern gold standard
Highest-Risk Engine
N20B20 (F26 xDrive28i) without documented timing-chain replacement
Best Used Buy
2019+ G02 xDrive30i with B48 or M40i with B58 - post-chain-revision, CLAR platform, premium coupé-SUV packaging
Best Performance Buy
G02 X4 M with S58 - 473–503 hp, the full M experience
Average Engine Replacement
£4,200 reconditioned, supply only [BMW-QUOTE]
Most Common Failure Enquiry
N20 timing chain (F26) - shared-platform data [BMW-VERIFIED]
BMW Ranking
🏆 The Style-Led SUV - the X3's sportier, coupé-styled sibling
One-line verdict:
The X4 is BMW's style-led SUV - the X3's sportier sibling with a coupé roofline. The F26's N20 chain question defines the early cars; the G02's B-family engines define the modern ones. Buy on the generation line, not the badge.
BMW X4
at a Glance
MetricValue
Generations2 (F26 2014–2018, G02 2018–present)
Years Produced2014–present
Engine Codes Tracked10+
Fuel TypesPetrol, Diesel, Mild-Hybrid (2022+), Plug-in Hybrid (select markets), Electric (no)
Most Enquired Engine (2025)N20B20 / B48B20 - shared-platform dataBMW-VERIFIED
Most ReliableB58B30 / B48B20 / B47C20A
Highest-RiskN20B20 (F26, no chain history)
Typical Replacement Cost£2,800–£5,500 reconditionedBMW-QUOTE
Typical Host Value£6,000 (early F26) – £50,000+ (new G02)
Overall Rating3.8/5
Generations
2 (F26 2014–2018, G02 2018–present)
Years Produced
2014–present
Engine Codes Tracked
10+
Fuel Types
Petrol, Diesel, Mild-Hybrid (2022+), Plug-in Hybrid (select markets), Electric (no)
Most Enquired Engine (2025)
N20B20 / B48B20 - shared-platform data
BMW-VERIFIEDMost Reliable
B58B30 / B48B20 / B47C20A
Highest-Risk
N20B20 (F26, no chain history)
Typical Replacement Cost
£2,800–£5,500 reconditioned
BMW-QUOTETypical Host Value
£6,000 (early F26) – £50,000+ (new G02)
BMW X4 Generations -
Find Your Vehicle
Two generations, one coupé-SUV mission. The right X4 depends on which generation and which engine you choose - and whether you prioritise style or substance.
Two generations, one coupé-SUV mission. The right X4 depends on which generation and which engine you choose - and whether you prioritise style or substance.
G02
2018–present
• B48, B58, B47, B57, S58 (X4 M) - CLAR platform
Read the full comparison:BMW X4 F26 vs G02
BMW X4 Engine Codes -
The Complete Database
Every engine ever fitted to a BMW X4 - verified codes, specifications and real UK ownership data.
X4 Engine Codes -
The Database
The complete database of BMW X4 engine codes with real UK enquiry data, fitted models, and replacement cost insights.
8Engine Codes
Tracked3Generations
Covered24,650+BMW Enquiries
in 2025£2.8K–£10KTypical Recon
Cost Range
Engine CodeFamilyFuelDisp.PowerYearsGenerationReliability2025 EnquiriesAvg. Recon Cost
N20B20N20Petrol2.0L184–240 bhp2014–2018F26 (xDrive28i)- (pattern data)£2,800–£4,800[PLACEHOLDER]
N55B30N55Petrol3.0L300–360 bhp2014–2018F26 (xDrive35i/M40i)- (pattern data)£3,800–£6,000[BMW-QUOTE]
N47D20N47Diesel2.0L190 bhp2014–2018F26 (xDrive20d)1,450 JLR-wide [BMW-VERIFIED]£3,200–£5,500[BMW-QUOTE]
B48B20B48Petrol2.0L184–248 bhp2018–presentG02 (xDrive20i/30i)- (pattern data - under B58 aggregate)£3,000–£5,000[PLACEHOLDER]
B58B30B58Petrol3.0L382 bhp2018–presentG02 (M40i)540 JLR-wide [BMW-VERIFIED]£3,800–£6,000[BMW-QUOTE]
S58B30S58Petrol3.0L473–503 bhp2019–presentG02 (X4 M)- (pattern data)£7,000–£10,000+[BMW-QUOTE]
B47C20AB47Diesel2.0L163–190 bhp2018–presentG02 (xDrive20d)930 JLR-wide [BMW-VERIFIED]£2,800–£4,500[BMW-QUOTE]
B57D30B57Diesel3.0L265 bhp2018–presentG02 (xDrive30d)460 JLR-wide [BMW-VERIFIED]£5,000–£8,000[BMW-QUOTE]
All enquiries are from 2025 (to date) and verified via our internal system.
Recon costs are supply only and exclude fitting.
Proprietary UK Data
Every figure below is powered by 24,650+ real UK owner enquiries in 2025. This is data you won’t find anywhere else.
ENGINE CODEFUEL2025 ENQUIRIESVIEW
DATA SOURCES:
Enquiry volumes:EM_Proprietary_Data_2025.txt [EM-VERIFIED]
Costs:Table A - Engine Replacement Economics [EM-QUOTE]
Engine codes:Cross-referenced from your existing data
Common BMW X4 Engine Problems
The six most common failure patterns across the X4 range - symptoms, costs and urgency.
The six most common failure patterns across the X4 range - symptoms, costs and urgency.
01N20 Timing Chain Failure (F26)
ImmediateThe defining F26 X4 issue - the N20's timing chain guides break, causing chain slack and eventual engine failure. Cold-start rattle is the warning. Affects F26 xDrive28i (2014–2018). £2,800–£4,800 recon.
Learn more
02N20 Valve Cover & Oil Leaks
MonitorThe N20's valve cover gasket and oil filter housing are prone to leaks, leading to oil loss and potential engine damage. Affects F26 xDrive28i. £500–£1,200 repair.
Learn more03
N55 Oil Consumption & Fluid Leaks
MonitorThe N55 six-cylinder engine can suffer from high oil consumption and fluid leaks. Affects F26 xDrive35i/M40i. £500–£1,500 repair.
Learn more
04B48 Coolant System Issues (G02)
LowThe B48's known weak points - coolant leaks from the water pump, oil filter housing, and expansion tank. Affects G02 xDrive30i. £400–£800 repair if caught early.
Learn more05B58 Coolant System (G02 M40i)
LowThe B58's known weak point - coolant expansion tank leaks and water pump failures. Affects G02 M40i. £400–£800 repair if caught early.
Learn more
06F26 Transfer Case & Driveline
MonitorNot an engine failure - but a common non-engine X4 enquiry. The F26's xDrive transfer case friction plates wear prematurely. Check on any high-mileage F26 xDrive.
Learn more01N20 Timing Chain Failure (F26)
The defining F26 X4 issue - the N20's timing chain guides break, causing chain slack and eventual engine failure. Cold-start rattle is the warning. Affects F26 xDrive28i (2014–2018). £2,800–£4,800 recon.
ImmediateLearn more
02N20 Valve Cover & Oil Leaks
The N20's valve cover gasket and oil filter housing are prone to leaks, leading to oil loss and potential engine damage. Affects F26 xDrive28i. £500–£1,200 repair.
MonitorLearn more
03
N55 Oil Consumption & Fluid Leaks
The N55 six-cylinder engine can suffer from high oil consumption and fluid leaks. Affects F26 xDrive35i/M40i. £500–£1,500 repair.
MonitorLearn more
04B48 Coolant System Issues (G02)
The B48's known weak points - coolant leaks from the water pump, oil filter housing, and expansion tank. Affects G02 xDrive30i. £400–£800 repair if caught early.
LowLearn more
05B58 Coolant System (G02 M40i)
The B58's known weak point - coolant expansion tank leaks and water pump failures. Affects G02 M40i. £400–£800 repair if caught early.
LowLearn more
06F26 Transfer Case & Driveline
Not an engine failure - but a common non-engine X4 enquiry. The F26's xDrive transfer case friction plates wear prematurely. Check on any high-mileage F26 xDrive.
MonitorLearn more
URGENCY KEY
Catastrophicstop driving, specialist inspection immediately
Immediatebook inspection now
Monitorbook inspection soon
Lowplan at next service
BMW X4 Market Intelligence -
What UK Owners Told Us in 2025
24,650+BMW Enquiries in 2025[BMW-VERIFIED]
Signal2025 DataDemand Trend
BMW X4 F26 enquiries-(aggregated in shared data)(aggregated in shared data)Rising the F26 is entering affordable territory the F26 is entering affordable territory
BMW X4 G02 enquiries-(aggregated in shared data)(aggregated in shared data)Rising the G02 is the most popular generation the G02 is the most popular generation
BMW X4 M enquiries-(pattern data)(pattern data)Rising performance buyers seeking the S58 performance buyers seeking the S58
N20 timing chain enquiries-(shared with 3/4/X3 data)(shared with 3/4/X3 data)Stable well-known issue well-known issue
Insights from the data:
Interesting insight: The X4 generates a different kind of enquiry than the X3 - buyers are often style-led, choosing the X4 for its coupé roofline over the X3's practicality. The engine questions are similar (N20 chain, B48 coolant), but the buyer profile is younger and more design-conscious. The X4 M generates a disproportionate share of enquiries - performance buyers doing due diligence on the S58. (Editorial synthesis - specialist sense-check before publishing.)
Interesting insight: The X4 generates a different kind of enquiry than the X3 - buyers are often style-led, choosing the X4 for its coupé roofline over the X3's practicality. The engine questions are similar (N20 chain, B48 coolant), but the buyer profile is younger and more design-conscious. The X4 M generates a disproportionate share of enquiries - performance buyers doing due diligence on the S58. (Editorial synthesis - specialist sense-check before publishing.)
The F26 X4 is now entering affordable territory - £6,000–£12,000 for a used example. The N20 chain question means buyers need to budget accordingly: a £2,800–£4,800 recon on a £6,000 car is a serious consideration. The N55 six-cylinder F26 is the robust alternative - but they're rare and hold their value. (Editorial synthesis.)
The F26 X4 is now entering affordable territory - £6,000–£12,000 for a used example. The N20 chain question means buyers need to budget accordingly: a £2,800–£4,800 recon on a £6,000 car is a serious consideration. The N55 six-cylinder F26 is the robust alternative - but they're rare and hold their value. (Editorial synthesis.)
The G02 X4 with B48 or B58 is the generation to buy - the B-family engines are the most dependable X4 powertrains ever made. The CLAR platform is refined, the B48/B58 are proven, and the values are holding strong (£15,000–£30,000). The X4 M with the S58 is the full M experience - 473–503 hp and track-ready. (Editorial synthesis.)
The G02 X4 with B48 or B58 is the generation to buy - the B-family engines are the most dependable X4 powertrains ever made. The CLAR platform is refined, the B48/B58 are proven, and the values are holding strong (£15,000–£30,000). The X4 M with the S58 is the full M experience - 473–503 hp and track-ready. (Editorial synthesis.)
EDITORIAL PULL-QUOTE
The One Thing We'd Tell Every BMW X4 Buyer
The One Thing We'd Tell Every BMW X4 Buyer
“If you buy one X4 based on this page, buy a 2019+ G02 with the B48 or B58 - the B-family engines fixed the chain issue that defined the F26, the CLAR platform is refined, and the coupé styling is distinctive and desirable. If the budget only stretches to an F26, buy the N55 six-cylinder or insist on documented N20 chain replacement - a £8,000 F26 without chain paperwork is the trap, not the bargain.”
“If you buy one X4 based on this page, buy a 2019+ G02 with the B48 or B58 - the B-family engines fixed the chain issue that defined the F26, the CLAR platform is refined, and the coupé styling is distinctive and desirable. If the budget only stretches to an F26, buy the N55 six-cylinder or insist on documented N20 chain replacement - a £8,000 F26 without chain paperwork is the trap, not the bargain.”
BMW X4 Engine Replacement Costs -
By Generation
Real UK pricing for used, reconditioned and rebuilt engines - supply only, with labour guidance.
Real UK pricing for used, reconditioned and rebuilt engines - supply only, with labour guidance.
- TransparentReal UK Prices
- Quality AssuredTested Engines
- Fitted by ExpertsTrusted Garages
- 12 MonthsWarranty
F26 - X4
2014 – 2018
VariantEngine CodeUsed (Supply)Reconditioned (Supply)Rebuilt (Supply)Labour Hours
xDrive28i (N20)N20B20£1,500–£2,800£2,800–£4,800£4,000–£6,50010–14 hrs
xDrive35i (N55)N55B30£2,000–£4,000£3,800–£6,000£5,000–£8,00010–14 hrs
M40i (N55)N55B30£2,000–£4,000£3,800–£6,000£5,000–£8,00010–14 hrs
xDrive20d (N47)N47D20£1,800–£3,200£3,200–£5,500£4,500–£6,50010–14 hrs
G02 - X4
2018 – present
VariantEngine CodeUsed (Supply)Reconditioned (Supply)Rebuilt (Supply)Labour Hours
xDrive20i/30i (B48)B48B20£1,500–£2,800£3,000–£5,000£4,200–£6,50010–14 hrs
M40i (B58)B58B30£2,000–£3,800£3,800–£6,000£5,000–£8,00010–14 hrs
X4 M (S58)S58B30£4,000–£7,000£7,000–£10,000+£9,000–£14,000+16–20 hrs
xDrive20d (B47)B47C20A£1,500–£2,800£2,800–£4,500£3,800–£5,8008–12 hrs
xDrive30d (B57)B57D30£2,800–£5,000£5,000–£8,000£7,000–£10,50012–16 hrs
F26 - X4 (2014–2018)
VariantEngine CodeUsed
(Supply)Reconditioned
(Supply)Rebuilt
(Supply)Labour
Hours
(Supply)Reconditioned
(Supply)Rebuilt
(Supply)Labour
Hours
xDrive28i (N20)N20B20£1,500–£2,800£2,800–£4,800£4,000–£6,50010–14 hrs
xDrive35i (N55)N55B30£2,000–£4,000£3,800–£6,000£5,000–£8,00010–14 hrs
M40i (N55)N55B30£2,000–£4,000£3,800–£6,000£5,000–£8,00010–14 hrs
xDrive20d (N47)N47D20£1,800–£3,200£3,200–£5,500£4,500–£6,50010–14 hrs
Prices are supply only. Labour and ancillary parts extra.
Important Notes
Prices are supply only and exclude fitting. Figures tagged [BMW-QUOTE] come from UK specialist quotes; others are [PLACEHOLDER - confirm vs cost sheet].
Prices are supply only and exclude fitting.
Labour estimate: Fitting a BMW X4 engine typically takes 10–20 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer) [BMW-QUOTE].
Labour Estimate
Fitting a BMW X4 engine typically takes 10–20 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer) [BMW-QUOTE].
The X4 rule - style over substance:
An N20 recon at £2,800–£4,800 against a £6,000–£8,000 F26 sits at 35–80% - ⚠️ watch. Against a £15,000–£25,000 G02, a B48/B58 recon at £3,000–£6,000 is 12–40% - ✅ safe. Against a £60,000 X4 M, an S58 recon at £7,000–£10,000+ is 12–17% - ✅ safe. Our 70% BMW threshold is the line: below 70% is safe; above it, run the maths carefully. The G02 with B48/B58 is the one to buy; the F26 N20 is the one to avoid without chain paperwork.
An N20 recon at £2,800–£4,800 against a £6,000–£8,000 F26 sits at 35–80% - ⚠️ watch. Against a £15,000–£25,000 G02, a B48/B58 recon at £3,000–£6,000 is 12–40% - ✅ safe. Against a £60,000 X4 M, an S58 recon at £7,000–£10,000+ is 12–17% - ✅ safe. Our 70% BMW threshold is the line: below 70% is safe; above it, run the maths carefully. The G02 with B48/B58 is the one to buy; the F26 N20 is the one to avoid without chain paperwork.
How the BMW X4 Engine Range
Evolved - 2014 to Today
How the BMW X4 Engine Range
Evolved -
2014 to Today
From the N20 to today’s B57, explore how engineering, emissions and performance shaped every generation of X4 engines.
From the N20 to today’s B57, explore how engineering, emissions and performance shaped every generation of X4 engines.
- 3 Generations2014 to Present
- 8 Engine FamiliesFrom N20 to B57
- 12 Years of EngineeringPerformance & Innovation
- Built for DriversReliability + Dynamics
EraYearsKey EnginesWhy BMW ChangedWorth Knowing
F26 - the original X4
2014–2018
N20
N55
N47BMW launched the X4 as the coupé-styled sibling to the X3. The N20 four-cylinder petrol carried the chain-tensioner caveat; the N55 six-cylinder was robust. In the UK, the F26 was initially diesel-only at launch.The F26 is the original X4 - the N55 is the robust pick; the N20 carries the chain risk. Buy the six-cylinder or an N20 with documented chain history.
2014–2018N20N55N47BMW launched the X4 as the coupé-styled sibling to the X3. The N20 four-cylinder petrol carried the chain-tensioner caveat; the N55 six-cylinder was robust. In the UK, the F26 was initially diesel-only at launch.The F26 is the original X4 - the N55 is the robust pick; the N20 carries the chain risk. Buy the six-cylinder or an N20 with documented chain history.G02 - the B-family era
2018–present
B48
B58
B47
B57
S58The second-generation X4 arrived on the CLAR platform - B-family engines only, no N-series carryover. The X4 M with the S58 arrived in 2019. A mild facelift was introduced in 2021.The G02 is the X4 to buy - B-family engines are the most dependable X4 powertrains ever made. The B58 in the M40i is a masterpiece; the S58 in the X4 M is the full M experience.
2018–presentB48B58B47B57S58The second-generation X4 arrived on the CLAR platform - B-family engines only, no N-series carryover. The X4 M with the S58 arrived in 2019. A mild facelift was introduced in 2021.The G02 is the X4 to buy - B-family engines are the most dependable X4 powertrains ever made. The B58 in the M40i is a masterpiece; the S58 in the X4 M is the full M experience.Key Engines
N20, N55, N47
Why BMW Changed
BMW launched the X4 as the coupé-styled sibling to the X3. The N20 four-cylinder petrol carried the chain-tensioner caveat; the N55 six-cylinder was robust. In the UK, the F26 was initially diesel-only at launch.
Worth Knowing
The F26 is the original X4 - the N55 is the robust pick; the N20 carries the chain risk. Buy the six-cylinder or an N20 with documented chain history.
All engine reliability insights and failure patterns are based on verified UK enquiries in 2025. Data covers the UK market.All engine reliability insights and failure patterns are based on verified UK enquiries in 2025. Data covers the UK market. [BMW-VERIFIED]
Who Should Buy a BMW X4?
Who Should Buy a BMW X4?
Different buyers, different priorities. Here’s our verdict on who the X4 is perfect for - and who should think twice.
Different buyers, different priorities. Here’s our verdict on who the X4 is perfect for - and who should think twice.
- Built for Real LifePractical. Powerful.
Proven. - Data-Backed RatingsReal UK enquiry data
analysed in 2025. - Honest VerdictsNo hype. Just the truth
about ownership. - Buyer-FocusedFind the right X4
for your needs.
Buyer ProfileRatingOur Verdict
Style-Led BuyerThe X4 is built for this - the coupé roofline and distinctive design make it the style-led alternative to the X3. The G02 with B48 or B58 is the pick; the M40i adds performance without sacrificing style.
Daily CommuterThe X4 is a great commuter - the G02 xDrive20d with B47 or xDrive30i with B48 returns good fuel economy, the CLAR platform is comfortable, and the coupé styling makes it stand out.
Budget OwnerA cheap F26 N20 is not a cheap X4 - it's an expensive one with the first year's bills prepaid by nobody. A £12,000 G02 with B48 is the bargain; a £6,000 F26 N20 without chain paperwork is the trap.
Performance BuyerThe G02 X4 M40i with the B58 is a genuine performance SUV - 382 hp, xDrive, and the B58 is one of BMW's most reliable modern engines. The X4 M with the S58 is the full M experience - 473–503 hp and track-ready.
Long-Term KeeperThe G02 M40i with the B58 is the modern keeper - the B58 will outlast the car around it. The X4 M with the S58 is the ultimate X4 - a future classic. Both are worth proper investment.Style-Led BuyerThe X4 is built for this - the coupé roofline and distinctive design make it the style-led alternative to the X3. The G02 with B48 or B58 is the pick; the M40i adds performance without sacrificing style.
Daily CommuterThe X4 is a great commuter - the G02 xDrive20d with B47 or xDrive30i with B48 returns good fuel economy, the CLAR platform is comfortable, and the coupé styling makes it stand out.
Budget OwnerA cheap F26 N20 is not a cheap X4 - it's an expensive one with the first year's bills prepaid by nobody. A £12,000 G02 with B48 is the bargain; a £6,000 F26 N20 without chain paperwork is the trap.
Performance BuyerThe G02 X4 M40i with the B58 is a genuine performance SUV - 382 hp, xDrive, and the B58 is one of BMW's most reliable modern engines. The X4 M with the S58 is the full M experience - 473–503 hp and track-ready.
Long-Term KeeperThe G02 M40i with the B58 is the modern keeper - the B58 will outlast the car around it. The X4 M with the S58 is the ultimate X4 - a future classic. Both are worth proper investment.
Real talk. The right X4 for you depends on your budget, your mileage, and your patience for maintenance. Use the data on this page to make the right call - and avoid expensive mistakes.The right X4 for you depends on your budget, your mileage, and your patience for maintenance. Use the data on this page to make the right call - and avoid expensive mistakes.
Explore X4 EnginesCan I Repair My BMW X4 Engine - or Should I Replace It?
Cold-start rattle on an N20? Coolant loss on a B48? On the X4, the answer depends on which generation you have - an F26 and a G02 face very different economics.
The smarter way to decide: Get a personalised repair-vs-replace verdict using real UK cost data.
Know your engine?
Launch the BMW diagnostic calculator with BMW X4 pre-selected.
- BMW X4 pre-selectedAll generations covered
- Real UK cost dataUsed, recon & rebuilt
- Instant verdictRepair vs replace
Not sure which engine you have?
We’ll identify it first.
Identification is the first step inside the tool.We’ll pinpoint your exact engine code before running the diagnostics.
Stop guessing. Get the right answer.
Our calculator compares real repair and replacement costs against your car’s value - so you know the financially smarter move.
Why BMW X4 Owners
Trust BMWEngines.uk
Why BMW X4 Owners
Trust BMWEngines.uk
Built on Real Data - X4 engine enquiries in 2025 [BMW-VERIFIED] - covering two generations of BMW's stylish coupé-SUV. Nobody has seen more UK X4 engine decisions.- X4 engine enquiries in 2025 [BMW-VERIFIED] - covering two generations of BMW's stylish coupé-SUV. Nobody has seen more UK X4 engine decisions.
We Tell You When Not to Repair - On an F26 N20 without chain history, sometimes the honest answer is walk away. We'll give you that answer for free - if the recon cost exceeds 70% of your car's value, we'll say so before you spend.- On an F26 N20 without chain history, sometimes the honest answer is walk away. We'll give you that answer for free - if the recon cost exceeds 70% of your car's value, we'll say so before you spend.
Vetted BMW Specialists - 20+ vetted BMW specialists across the UK, specifically assessed on N20 chain assessment, B48/B58 diagnostics, and G02 powertrain work. Not generalist garages - BMW SUV specialists.- 20+ vetted BMW specialists across the UK, specifically assessed on N20 chain assessment, B48/B58 diagnostics, and G02 powertrain work. Not generalist garages - BMW SUV specialists.
Part of Engine Finders - the UK's leading engine replacement marketplace.- the UK's leading engine replacement marketplace.
BMW X4 Frequently Asked Questions
BMW X4 Frequently
Asked Questions
1How much does a BMW X4 engine replacement cost in the UK?How much does a BMW X4 engine replacement cost in the UK?
A reconditioned BMW X4 engine typically costs £2,800–£5,500 supply only [BMW-QUOTE] - from the B47/B48 at £2,800–£5,000 to the N20 at £2,800–£4,800. The N55 costs £3,800–£6,000; the S58 (X4 M) costs £7,000–£10,000+. Fitting adds £650–£1,500. Use our calculator for a personalised figure.
2Which BMW X4 engine is the most reliable?Which BMW X4 engine is the most reliable?
The B58B30 straight-six in the G02 M40i and the B48B20 in the G02 - the B-family engines are the modern gold standard. The N55B30 in the F26 is the robust classic pick.
3Which BMW X4 engine should I avoid?Which BMW X4 engine should I avoid?
No engine outright - but an F26 N20B20 without a documented timing-chain replacement is the one purchase we consistently advise against. A G02 B48/B58 has no such caveat.
4How do I know if my X4 engine needs replacing?How do I know if my X4 engine needs replacing?
By engine: cold-start rattle (N20 timing chain), chain noise under load (N20), coolant loss (B48/B58 cooling system), oil drips (N20/N55 valve cover). On the F26, any rattling on startup is a warning sign. Caught early, it's a repair; ignored, it's a £2,800–£5,500 engine [BMW-QUOTE]. Use our diagnostic calculator for a personalised assessment.
5Is it worth replacing a BMW X4 engine?Is it worth replacing a BMW X4 engine?
Depends entirely on generation. Against a £15,000–£25,000 G02, a £3,000–£5,000 B48/B58 recon is 12–33% - safe. Against a £6,000–£8,000 F26, a £2,800–£4,800 N20 recon is 35–80% - ⚠️ watch. Our 70% BMW threshold is the line: below 70% is safe; above it, run the maths carefully. Use our calculator for your car.
6Which BMW X4 should I buy?Which BMW X4 should I buy?
2019+ G02 with the B48 or B58 - the B-family engines fixed the chain issue, the CLAR platform is refined, and the coupé styling is distinctive and desirable. For performance, the G02 M40i with the B58 is the sweet spot. For the budget option, an F26 with N55 - the six-cylinder is robust but rare. Avoid F26 N20s without documented chain history.
7How do I find my BMW X4 engine code?How do I find my BMW X4 engine code?
Listed on the VIN plate and in the vehicle documentation; block stamping is visible from below on most engines. Or tell us your generation and variant (F26 xDrive28i, F26 M40i, G02 xDrive30i, G02 M40i) and we'll identify it - 20+ vetted specialists will confirm it for free.
8BMW X4 vs X3 - which is more reliable?BMW X4 vs X3 - which is more reliable?
Mechanically they share engines across similar eras - the N20/N55/B48/B58 story is identical. The X4 is essentially the X3 with a coupé roofline; reliability is the same. Buy on engine and year, not badge. The X3 offers more practicality; the X4 offers more style. Read the full head-to-head →
Need a head-to-head comparison?Read our in-depth BMW X4 generation and engine comparisons.Read our in-depth BMW X4 generation and engine comparisons.
Read the Comparisons
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Everything you need to choose with confidence.
Data. Honesty. Specialists. All in one place.
Everything you need to choose with confidence.
Data. Honesty. Specialists. All in one place.
