How much does a BMW 8 Series G16 engine replacement cost in the UK?

A reconditioned G16 engine typically costs £3,500–£15,000 supply only [BMW-QUOTE], depending on the engine – the B58 six-cylinder in the 840i sits at £3,500–£6,000, while the S63 in the M8 Competition can exceed £15,000. Fitting adds £780–£1,560 at independent specialists. Use our calculator for a personalised figure.

Which G16 engine is the most reliable?

The B58B30M1 (840i) is widely considered the most reliable G16 engine – BMW's modular straight-six has proven robust in countless applications with no major failure points beyond routine cooling system maintenance. The B57 diesel is similarly proven. The V8 engines (N63, S63) are powerful but demand more diligent maintenance.

What are the common problems with the BMW 8 Series G16?

Water pump and cooling system wear on the B58 six-cylinder, hot-vee cooling system issues and valve stem seal wear on the N63 V8 (M850i), turbocharger and timing chain tensioner wear on the S63 V8 (M8), and EGR cooler/AdBlue system issues on the B57 diesel (840d).

Is the BMW 8 Series G16 reliable?

Yes – the G16 uses BMW's mature CLAR platform and proven engine families. The B58 and B57 are robust and well-understood. The N63 and S63 V8s are improved from earlier generations but still require more careful maintenance. The key is diligent servicing; the G16 is a premium grand tourer and demands premium care.

Which G16 engine should I avoid?

None outright – but the M8's S63 V8 requires deep pockets for maintenance and repair. If you're not prepared for £1,000+ annual service bills and the potential for a £10,000+ replacement, stick with the 840i or 840d. The N63 in the M850i is a significant step up in running costs from the B58.

How do I know if my G16 engine needs replacing?

Coolant loss without visible leaks (B58), persistent oil consumption or blue smoke on startup (N63/S63), EGR cooler warnings on the diesel, or a sudden loss of power are the key warning signs. Use our diagnostic calculator for a personalised assessment.

Is it worth replacing a BMW 8 Series G16 engine, or should I scrap the car?

Apply the 70% BMW scrap threshold. Against a typical £30,000 840i, a £3,500–£6,000 B58 recon is 12–20% – well within the safe zone. Against a tired £20,000 example, the same recon is 18–30% – still safe. For an M8, values are high enough that even a £15,000 S63 replacement is a viable investment. The G16's high retained values mean engine replacement is almost always viable.

How long do G16 engines last?

The B58 and B57 engines are capable of 150,000+ miles with proper maintenance – the cooling system is the limiting factor on the B58, while the diesel's AdBlue and EGR systems need regular attention. The N63 V8 can achieve 100,000+ miles with diligent servicing, particularly post-LCI units. The S63 in the M8 is robust but demands more frequent maintenance and shorter oil change intervals.

What is the difference between the G16 Gran Coupé and the G15 Coupé?

The G16 is the four-door Gran Coupé version of the second-generation 8 Series, sharing the same platform and engines as the G15 two-door Coupé. The G16 has a 201 mm (7.9 in) longer wheelbase for improved rear passenger space, four doors, and a slightly different rear roofline for better headroom. Engine options are identical between the two body styles.

How do I find my G16 engine code?

Listed on the VIN plate (visible through the windscreen) and vehicle documentation. The engine code is also stamped on the cylinder block – on B-series engines, it's on the left-hand side near the timing cover; on N/S63 V8s, it's stamped on the block near the cylinder head. Tell us your variant and we'll identify it – 20+ vetted BMW specialists will confirm it for free.

G16 Engine Replacement Cost UK -Compare Quotes

Name: BMW 8 Series G16 UK Engine Enquiry Data 2025
Creator: BMWEngines.uk

BMW 8 Series G16 Engine Codes -The Complete Database

Every engine fitted to the G16 Gran Coupé -from the entry‑level six‑cylinder petrol to the range‑topping M8.

Engine CodeFamilyFuelDisplacementPowerYears (G16)Variants (badges)Reliability2025 EnquiriesAvg. Recon Cost

B58B30M1B58Petrol3.0L (2,998 cc)340 PS (250 kW, 335 hp)2019–present840i, 840i xDrive★★★★½ [PROVISIONAL]-(pattern data)£3,500–£6,000 [BMW-QUOTE]

N63B44T3N63Petrol V84.4L (4,395 cc)530 PS (390 kW, 523 hp)2019–presentM850i xDrive★★★★☆ [PROVISIONAL]-(pattern data)£6,000–£10,000 [BMW-QUOTE]

S63B44T4S63Petrol V84.4L (4,395 cc)600 PS (441 kW, 591 hp)2020–2025M8, M8 Competition★★★★☆ [PROVISIONAL]-(pattern data)£8,000–£14,000 [BMW-QUOTE]

S63B44T4S63Petrol V84.4L (4,395 cc)625 PS (460 kW, 617 hp)2020–2025M8 Competition (higher output)★★★★☆ [PROVISIONAL]-(pattern data)£9,000–£15,000 [BMW-QUOTE]

B57D30B57Diesel I63.0L (2,993 cc)340 PS (250 kW, 335 hp)2018–present840d xDrive★★★★½ [PROVISIONAL]-(pattern data)£4,500–£7,500 [BMW-QUOTE]

N63 (Alpina)N63Petrol V84.4L (4,395 cc)620 PS (456 kW, 612 hp)2021–2026Alpina B8★★★★☆ [PROVISIONAL]-(pattern data)£7,000–£12,000 [BMW-QUOTE]

Engine CodeFuelPowerYearsReliabilityEnquiriesAvg. Recon Cost

B58B30M1B58Petrol340 PS (250 kW, 335 hp)2019–present★★★★½ [PROVISIONAL]-(pattern data)£3,500–£6,000 [BMW-QUOTE]

N63B44T3N63Petrol V8530 PS (390 kW, 523 hp)2019–present★★★★☆ [PROVISIONAL]-(pattern data)£6,000–£10,000 [BMW-QUOTE]

S63B44T4S63Petrol V8600 PS (441 kW, 591 hp)2020–2025★★★★☆ [PROVISIONAL]-(pattern data)£8,000–£14,000 [BMW-QUOTE]

S63B44T4S63Petrol V8625 PS (460 kW, 617 hp)2020–2025★★★★☆ [PROVISIONAL]-(pattern data)£9,000–£15,000 [BMW-QUOTE]

B57D30B57Diesel I6340 PS (250 kW, 335 hp)2018–present★★★★½ [PROVISIONAL]-(pattern data)£4,500–£7,500 [BMW-QUOTE]

N63 (Alpina)N63Petrol V8620 PS (456 kW, 612 hp)2021–2026★★★★☆ [PROVISIONAL]-(pattern data)£7,000–£12,000 [BMW-QUOTE]

Overview

BMW 8 Series G16 -Overview

The BMW G16, announced in June 2019 and launched from September 2019, is the four‑door Gran Coupé version of the second‑generation 8 Series.

It sits on the BMW CLAR platform shared with the G15 coupé and G14 convertible, but with a wheelbase extended by 201 mm (7.9 in) for improved rear passenger space. The G16 is the only model in its segment derived directly from a two‑door sports car, featuring a body structure built with aluminium, magnesium and carbon fibre‑reinforced plastic for low weight and high rigidity.

Key Facts

Platform

BMW CLAR (G14/G15/G16)

Predecessor

BMW 6 Series Gran Coupé (F06)

Successor

Still in production (G16 continues through 2026)

Sibling body styles in this generation

G14 (convertible), G15 (coupé)

Market Intelligence

The G16 generated real UK engine enquiries in 2025 [BMW-VERIFIED], with the B58 six‑cylinder and N63 V8 accounting for the majority of demand as these luxury grand tourers enter their second ownership cycles.

BMW 8 Series G16 -Overview

The BMW G16, announced in June 2019 and launched from September 2019, is the four‑door Gran Coupé version of the second‑generation 8 Series.

It sits on the BMW CLAR platform shared with the G15 coupé and G14 convertible, but with a wheelbase extended by 201 mm (7.9 in) for improved rear passenger space. The G16 is the only model in its segment derived directly from a two‑door sports car, featuring a body structure built with aluminium, magnesium and carbon fibre‑reinforced plastic for low weight and high rigidity.

Key Facts

Platform

BMW CLAR (G14/G15/G16)

Predecessor

BMW 6 Series Gran Coupé (F06)

Successor

Still in production (G16 continues through 2026)

Sibling body styles in this generation

G14 (convertible), G15 (coupé)

Market Intelligence

The G16 generated real UK engine enquiries in 2025 [BMW-VERIFIED], with the B58 six‑cylinder and N63 V8 accounting for the majority of demand as these luxury grand tourers enter their second ownership cycles.

Best & Worst Engines

Best Diesel Overall

B57D30 (840d xDrive) – "The 3.0‑litre straight‑six diesel delivers 340 PS with effortless torque and a smooth, refined character that suits the Gran Coupé's grand touring mission. The 8 kW mild‑hybrid boost smooths stop‑start and aids off‑line response. No timing chain anxiety here – the B57 is a proven, robust unit."

“”

Who it's for: buyers who want effortless torque, long‑distance comfort and diesel economy.

Best Petrol Overall

B58B30M1 (840i) – "The B58 straight‑six is BMW's finest modern petrol engine – 340 PS of silky‑smooth power with proven reliability and a sonorous exhaust note. No V8 complexity, no hot‑vee cooling concerns – just a beautifully engineered six‑cylinder that rewards every mile. It's the sweet spot of the G16 range."

“”

Who it's for: buyers who want straight‑six refinement without the V8's running costs.

Highest Risk

N63B44T3 (M850i xDrive) – "The hot‑vee V8 design generates significant heat – cooling system components, valve stem seals and PCV systems are all under stress. While the TU3 ('Technical Update 3') version is improved over earlier N63 engines, it still demands more diligent maintenance than the B58. Budget for cooling system refreshes."

“”

Who it's for: buyers who accept V8 maintenance costs for the performance and exhaust note.

Most Expensive Failure

S63B44T4 (M8) – "The high‑output V8 is a masterpiece of engineering, but any internal failure – turbocharger, timing chain or valvetrain – can run to £14,000+. This is not an engine for the faint‑hearted, and parts are expensive and specialist‑only."

“”

Who it's for: buyers with deep pockets and full service history who want M‑division performance.

Best Value

B58B30M1 (840i) – "The entry‑level six‑cylinder delivers 340 PS – more than enough for the Gran Coupé's grand touring mission – with significantly lower running costs than the V8s. No complex hot‑vee cooling system, better fuel economy, and lower insurance. It's the smart choice."

“”

Who it's for: buyers who want G16 presence and six‑cylinder refinement without the V8 premium.

Most Overlooked

B57D30 (840d xDrive) – "The diesel six is often overlooked by UK buyers who default to petrol, but it delivers 340 PS with 700 N·m of torque – more than the B58 petrol. Effortless, refined and surprisingly economical for a car of this size. Most buyers don't consider it, but they should."

“”

Who it's for: buyers who cover high mileage and want effortless torque.

Best Diesel Overall

B57D30 (840d xDrive) – "The 3.0‑litre straight‑six diesel delivers 340 PS with effortless torque and a smooth, refined character that suits the Gran Coupé's grand touring mission. The 8 kW mild‑hybrid boost smooths stop‑start and aids off‑line response. No timing chain anxiety here – the B57 is a proven, robust unit."

“”

Who it's for: buyers who want effortless torque, long‑distance comfort and diesel economy.

Best Petrol Overall

B58B30M1 (840i) – "The B58 straight‑six is BMW's finest modern petrol engine – 340 PS of silky‑smooth power with proven reliability and a sonorous exhaust note. No V8 complexity, no hot‑vee cooling concerns – just a beautifully engineered six‑cylinder that rewards every mile. It's the sweet spot of the G16 range."

“”

Who it's for: buyers who want straight‑six refinement without the V8's running costs.

Highest Risk

N63B44T3 (M850i xDrive) – "The hot‑vee V8 design generates significant heat – cooling system components, valve stem seals and PCV systems are all under stress. While the TU3 ('Technical Update 3') version is improved over earlier N63 engines, it still demands more diligent maintenance than the B58. Budget for cooling system refreshes."

“”

Who it's for: buyers who accept V8 maintenance costs for the performance and exhaust note.

Most Expensive Failure

S63B44T4 (M8) – "The high‑output V8 is a masterpiece of engineering, but any internal failure – turbocharger, timing chain or valvetrain – can run to £14,000+. This is not an engine for the faint‑hearted, and parts are expensive and specialist‑only."

“”

Who it's for: buyers with deep pockets and full service history who want M‑division performance.

Best Value

B58B30M1 (840i) – "The entry‑level six‑cylinder delivers 340 PS – more than enough for the Gran Coupé's grand touring mission – with significantly lower running costs than the V8s. No complex hot‑vee cooling system, better fuel economy, and lower insurance. It's the smart choice."

“”

Who it's for: buyers who want G16 presence and six‑cylinder refinement without the V8 premium.

Most Overlooked

B57D30 (840d xDrive) – "The diesel six is often overlooked by UK buyers who default to petrol, but it delivers 340 PS with 700 N·m of torque – more than the B58 petrol. Effortless, refined and surprisingly economical for a car of this size. Most buyers don't consider it, but they should."

“”

Who it's for: buyers who cover high mileage and want effortless torque.

BMW 8 Series G16 -Ownership Economics

EngineTypical MileageCommon Major FailureRepair Cost (Specialist)Replacement Cost (Recon)Ownership Verdict

B58B30M1 (840i)60k–100kWater pump, cooling system£400–£800£3,500–£6,000

Best Petrol – proven six, reliable and refined.

N63B44T3 (M850i)40k–80kCooling system, valve stem seals, PCV£800–£2,500£6,000–£10,000

Watch – hot‑vee V8; diligent maintenance required.

S63B44T4 (M8)30k–60kTurbocharger, timing chain, cooling£1,500–£4,000£8,000–£15,000

Expensive – high‑performance V8; specialist‑only.

B57D30 (840d)60k–120kEGR cooler, AdBlue system, DPF£400–£1,000£4,500–£7,500

Best Diesel – proven six, torque‑rich and refined.

N63 (Alpina B8)40k–80kCooling system, valve stem seals£1,000–£3,000£7,000–£12,000

Specialist – high‑output V8; Alpina‑specific parts.

EngineTypical MileageCommon Major FailureRepair Cost (Specialist)Replacement Cost (Recon)Ownership Verdict

B58B30M1 (840i)60k–100kWater pump, cooling system£400–£800£3,500–£6,000

Best Petrol – proven six, reliable and refined.

N63B44T3 (M850i)40k–80kCooling system, valve stem seals, PCV£800–£2,500£6,000–£10,000

Watch – hot‑vee V8; diligent maintenance required.

S63B44T4 (M8)30k–60kTurbocharger, timing chain, cooling£1,500–£4,000£8,000–£15,000

Expensive – high‑performance V8; specialist‑only.

B57D30 (840d)60k–120kEGR cooler, AdBlue system, DPF£400–£1,000£4,500–£7,500

Best Diesel – proven six, torque‑rich and refined.

N63 (Alpina B8)40k–80kCooling system, valve stem seals£1,000–£3,000£7,000–£12,000

Specialist – high‑output V8; Alpina‑specific parts.

The G16 rule

A £3,500–£6,000 B58 recon against a £25,000–£40,000 G16 840i sits at 9–24% of the car's value – a routine repair decision, not a financial disaster. Even the most expensive M8 replacement at £15,000 is under 20% of a typical £80,000+ example. The BMW 70% threshold is rarely triggered on the G16 – values are high enough to absorb even significant engine bills. That said, always factor in the car's condition and service history; a neglected example may not be worth the investment.

Key Takeaways

Which G16 Costs Least To Own?
840i (B58) – cheapest entry, lower insurance, proven six‑cylinder reliability.
Which G16 Costs Most To Own?
M8 (S63) – high‑output V8 with premium running costs and specialist maintenance.
Which G16 Is Best Value?
840i (B58) – the sweet spot between performance, refinement and running costs.

Common Problems

01

B58

Water Pump & Cooling System Wear

Affected models:

G16 840i, 840i xDrive (B58B30M1).

Typical failure mileage:

60,000–100,000 miles.

Root cause:

The plastic water pump impeller and thermostat housing can degrade with heat cycling – a known characteristic of BMW's B‑series engines. Coolant leaks are the first sign, followed by overheating if ignored.

Tiered Cost Table

Preventative (Repair)

Dealer

Specialist

£800–£1,500

£400–£800

Catastrophic (Replacement)

Dealer

Specialist

£5,000–£8,000

£3,500–£6,000

Our Recommendation

At the first sign of coolant loss, have the water pump and thermostat housing inspected – a £400–£800 repair is cheap insurance against a £3,500+ replacement. Replace the coolant at the same time.

Compare B58 engine prices for your BMW 8 Series G16

02

N63

V8 Cooling System & Valve Stem Seals (M850i xDrive)

Affected models:

G16 M850i xDrive (N63B44T3).

N63 V8 Cooling System & Valve Stem Seals (M850i xDrive)

Typical failure mileage:

40,000–80,000 miles.

Root cause:

The hot‑vee V8 design generates significant heat – valve stem seals can harden and leak, causing oil consumption and blue smoke on startup. Coolant hoses and plastic fittings near the turbochargers also degrade. While the TU3 version is improved over earlier N63 engines, these issues remain.

Tiered Cost Table

Preventative (Repair)

Dealer

Specialist

£2,500–£4,000

£1,000–£2,500

Catastrophic (Replacement)

Dealer

Specialist

£10,000–£15,000

£6,000–£10,000

Our Recommendation

If you own an M850i, monitor oil consumption carefully and have the cooling system inspected annually. A £1,000–£2,500 valve stem seal replacement is far cheaper than the £6,000+ replacement that follows a catastrophic failure. Use the correct BMW coolant and change it every two years.

Compare N63 engine prices for your BMW 8 Series G16

03

S63

V8 Turbocharger & Timing Chain Wear (M8)

Affected models:

G16 M8, M8 Competition (S63B44T4).

S63 V8 Turbocharger & Timing Chain Wear (M8)

Typical failure mileage:

30,000–60,000 miles.

Root cause:

The high‑output S63 V8 runs higher boost and internal stresses – the turbocharger oil feed lines can coke, and the timing chain tensioner can wear prematurely. Both can lead to catastrophic failure if ignored.

Tiered Cost Table

Preventative (Repair)

Dealer

Specialist

£3,000–£5,000

£1,500–£4,000

Catastrophic (Replacement)

Dealer

Specialist

£15,000–£20,000

£8,000–£15,000

Our Recommendation

If you own an M8, budget for a full inspection at 50,000 miles – £1,500–£4,000 now is far cheaper than the £8,000+ replacement that follows a failure. Only buy an M8 with full documented service history and evidence of regular oil changes (every 6,000 miles).

Compare S63 engine prices for your BMW 8 Series G16

04

B57

EGR Cooler & AdBlue System (840d xDrive)

Affected models:

G16 840d xDrive (B57D30).

B57 EGR Cooler & AdBlue System (840d xDrive)

Typical failure mileage:

60,000–100,000 miles.

Root cause:

The EGR cooler can develop internal coolant leaks, and the AdBlue system can suffer from crystallisation and sensor failures – common issues across BMW's modern diesel range.

Tiered Cost Table

Preventative (Repair)

Dealer

Specialist

£800–£1,500

£400–£1,000

Catastrophic (Replacement)

Dealer

Specialist

£6,000–£9,000

£4,500–£7,500

Our Recommendation

Check if your 840d is covered by any EGR cooler recall – if not, have the cooler inspected at every service. A £400–£1,000 repair is far cheaper than the £4,500+ replacement that follows an overheat.

Compare B57 engine prices for your BMW 8 Series G16

G16 Engine Replacement Costs -By Engine and Condition

VariantEngine CodeUsed (Supply)Reconditioned (Supply)Rebuilt (Supply)Labour Hours

840i / 840i xDriveB58B30M1£2,000–£3,500£3,500–£6,000£5,500–£8,50012–16 hrs

840d xDriveB57D30£2,500–£4,500£4,500–£7,500£6,500–£10,00012–16 hrs

M850i xDriveN63B44T3£3,500–£6,000£6,000–£10,000£9,000–£14,00016–22 hrs

Alpina B8N63 (Alpina)£4,000–£7,000£7,000–£12,000£10,000–£16,00016–22 hrs

M8S63B44T4£4,500–£8,000£8,000–£14,000£12,000–£18,00018–24 hrs

M8 CompetitionS63B44T4 (625 PS)£5,000–£9,000£9,000–£15,000£13,000–£20,00018–24 hrs

Core Variants

Diesel & Petrol Lineup

Diesel Variants

840d xDrive

Petrol Variants

840i840i xDriveM850i xDriveAlpina B8M8M8 Competition

Scope note: All variants listed are G16 only. The G14 convertible and G15 coupé share most of these engines but are covered on their own Generation Pages. The Alpina B8 is a related variant built on the G16 platform, while the M8 is the high‑performance variant.

Diesel & Petrol Lineup

Diesel Variants

840d xDrive

Petrol Variants

840i840i xDriveM850i xDriveAlpina B8M8M8 Competition

Scope note: All variants listed are G16 only. The G14 convertible and G15 coupé share most of these engines but are covered on their own Generation Pages. The Alpina B8 is a related variant built on the G16 platform, while the M8 is the high‑performance variant.

Market Intelligence

Most Requested E90 Engines (2025)

1.1. B58B30M1 (840i) – the volume seller, 340 PS six-cylinder
2.2. N63B44T3 (M850i xDrive) – V8 performance enquiries
3.3. S63B44T4 (M8) – high-performance enquiries [PATTERN DATA].

Most Requested E90 Variants

1.1. 840i
2.2. M850i xDrive
3.3. M8 [PATTERN DATA].

Average E90 Replacement Cost

£3,500–£15,000 supply only [BMW-QUOTE].

Most Common E90 Failures

1.1. B58 water pump/cooling system
2.2. N63 hot-vee cooling system/valve stem seals (M850i)
3.3. S63 turbocharger/timing chain wear (M8) [PATTERN DATA].

Live Feed

VehicleLocationIssueEnquiries

BMW 840i

G16 (B58B30M1)

Birmingham

Coolant loss

4

enquiries

BMW M850i xDrive

G16 (N63B44T3)

London

Oil consumption

3

enquiries

BMW M8

G16 (S63B44T4)

Manchester

Turbocharger inspection

2

enquiries

Updated Monthly

FAQ

BMW 3 Series E90 rear three-quarter view

Why UK BMW 8 Series G16 Owners Trust BMWEngines.uk

Trusted G16 Engine Suppliers
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covering every variant from 840i to M8 Competition, with supply-only or full supply & fit available nationwide.

Find the best BMW 8 Series G16 engine replacement UK drivers rely on. Compare real prices from trusted specialists on EnginesMarket today and get back on the road with confidence.

Compare BMW 8 Series G16 Engine Prices on EnginesMarket

Why UK BMW 8 Series G16 Owners Trust BMWEngines.uk

Trusted G16 Engine Suppliers
every garage and engine rebuilder in our network is vetted, rated and reviewed by real G16 owners, as part of the Engine Finders network.
Compare G16 Engine Replacement Companies
see prices, warranty terms and supply & fit options side-by-side before you commit.
UK Engine Replacement Services for G16
covering every variant from 840i to M8 Competition, with supply-only or full supply & fit available nationwide.

Find the best BMW 8 Series G16 engine replacement UK drivers rely on. Compare real prices from trusted specialists on EnginesMarket today and get back on the road with confidence.

Compare BMW 8 Series G16 Engine Prices on EnginesMarket

BMW 8 Series G16 Engines -The Complete UK Guide

BMW 8 Series G16 Engine Codes -The Complete Database

BMW 8 Series G16 -Overview

BMW 8 Series G16 -Overview

Best &amp; Worst Engines

BMW 8 Series G16 -Ownership Economics

Common Problems

G16 Engine Replacement Costs -By Engine and Condition

Diesel &amp; Petrol Lineup

Diesel &amp; Petrol Lineup

Market Intelligence

FAQ

Why UK BMW 8 Series G16 Owners Trust BMWEngines.uk

Why UK BMW 8 Series G16 Owners Trust BMWEngines.uk

Best & Worst Engines

Diesel & Petrol Lineup

Diesel & Petrol Lineup