How much does a BMW 8 Series 840i engine replacement cost in the UK?

A reconditioned 840i engine typically costs £2,500–£7,500 supply only depending on generation, with the E31 V8s lower and the B58 higher. Fitting adds £1,000–£1,800. Use our calculator for a figure specific to your 840i.

Is the BMW 840i engine reliable?

It depends which generation your 840i is. The E31 M62 is the most reliable V8 with timing chain guides as its main weakness. The B58 is widely regarded as one of BMW's most reliable modern engines. The E31 M60 is the most maintenance‑sensitive. Check the Era Map above for your specific car.

What are the common problems with the BMW 840i engine?

E31 M60: Nikasil liner degradation. E31 M62: timing chain guide failure. G14/G15/G16 B58: coolant loss (water pump, expansion cap), PCV valve failure, and oil filter housing leaks. Each generation has its own character and watchpoints.

Is it worth replacing an 840i engine, or should I scrap the car?

Depends on vehicle value and generation. An E31 840i is a classic - values range from £8,000–£30,000, making replacement viable in many cases. A G14/G15/G16 840i is a £25,000–£60,000 vehicle - a £5,000–£7,000 recon is 8–28% of the car's value, making replacement a clear decision. Evaluate carefully based on your car's generation and condition.

How do I find my BMW 840i engine code?

Listed on the VIN plate and vehicle documentation. The 840i covers M60 (E31 1993–1996), M62 (E31 1996–1999), B58B30M1 (G14/G15/G16 2018–2022), and B58B30C (G14/G15/G16 LCI 2022+). Tell us your registration date and we'll confirm which one you have for free.

Can I prevent the common failures on an 840i?

On E31 M60: use low‑sulphur fuel and have compression tested periodically. On E31 M62: timing chain guides replacement at 100,000 miles is recommended. On B58: regular coolant system checks, BMW‑spec oil changes, and PCV system inspections are the most effective prevention. At the first sign of rattle, coolant loss or rough running, book an inspection immediately.

BMW 8 Series 840i1993–presentM60 / M62 / B58

BMW 8 Series 840i Engine Replacement — Compare Prices & Get Quotes

The 840i badge spans two distinct eras of BMW's grand tourer - the classic E31 V8 and the modern G14/G15/G16 B58 straight-six. Get quotes from trusted UK specialists today.

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8 Series 840i Engines - from £1,000 to £8,500M60 / M62 / B58

8 Series 840i Engines - from £1,000 to £8,500· M60 / M62 / B58

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The 840i THROUGH TIME - Era Map

Four generations. Four eras. One guide to reliability, costs and what really matters.

GenerationYearsEngine CodeReliabilityRecon CostEra Note

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.

Real UK Cost Data

Verified Reliability

Expert Insights

Updated for 2025

BMW 8 Series 840i Engine Replacement Costs

Supply Only£2,500–£7,500

Fitted (Indie)£3,500–£9,000

Warranty12–24 months

Best ForMost owners - best cost/warranty balance

Engine TypeSupply OnlyFitted (Indie)WarrantyBest For

Used Engine£1,000–£4,500£1,800–£6,0001–6 monthsBudget priority; older generations

Reconditioned Engine£2,500–£7,500£3,500–£9,00012–24 monthsMost owners - best cost/warranty balance

Rebuilt Engine£3,500–£8,500£4,500–£10,00012–24 monthsLong-term ownership; 3+ year horizon

Main Dealer New£6,000–£12,000 (where available)£7,200–£13,80024–36 monthsInsurance jobs, warranty claims

Figures above reflect the range across all generations; specific costs vary by era - see the Era Map above.

Labour estimate: Fitting an 840i engine typically takes 12–18 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer).

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Common Problems With BMW 320d Engines

1. Nikasil Cylinder Liner Degradation (M60, E31 1993–1996)

Symptoms: Misfires, rough idle, loss of compression, increased oil consumption, engine warning light.

Typical mileage: 60,000–100,000 miles

Repair cost: £3,000–£6,000 (engine rebuild or replacement)

Replacement cost: £3,000–£6,000 (full engine replacement)

🟠 Check - book inspection urgently if misfires occur

Our recommendation:

The M60 V8's Nikasil cylinder liners can degrade when exposed to high‑sulphur fuel. If you experience misfires or rough running, have a compression test performed immediately. Many early M60 engines have been replaced; if yours hasn't, budget for a bottom‑end rebuild or replacement.

1. Nikasil Cylinder Liner Degradation (M60, E31 1993–1996)

Symptoms: Misfires, rough idle, loss of compression, increased oil consumption, engine warning light.

Typical mileage: 60,000–100,000 miles

Repair cost: £3,000–£6,000 (engine rebuild or replacement)

Replacement cost: £3,000–£6,000 (full engine replacement)

🟠 Check - book inspection urgently if misfires occur

Our recommendation:

2. Timing Chain Guide Failure (M62, E31 1996–1999)

Symptoms: Rattling noise on cold start, metallic ticking, engine warning light, loss of power.

Typical mileage: 80,000–150,000 miles

Repair cost: £1,500–£3,500 (chain guides and tensioner replacement)

Replacement cost: N/A - repair only (if caught before chain jumps)

🔴 Immediate - if you hear rattle, book an inspection today

Our recommendation:

The M62's timing chain guides are the defining weakness - they become brittle and can shatter, causing the chain to jump. If you hear a rattling noise on cold start, have the guides inspected immediately. Regular oil changes with the correct spec are essential. Many owners replace the guides preventatively around 100,000 miles.

3. Coolant Loss (B58, G14/G15/G16 2018+)

Symptoms: Low coolant warning light, sudden drop in coolant level, overheating, visible coolant puddles under the car.

Typical mileage: 40,000–80,000 miles

Repair cost: £400–£900 (water pump or expansion tank/cap replacement) [PLACEHOLDER - confirm vs cost sheet]

Replacement cost: N/A - repair only

🟠 Check - book inspection urgently if coolant levels drop

Our recommendation:

B58 coolant loss is one of the most frequently reported issues. The electric water pump can fail, and the expansion tank cap may not seal properly. If you notice the coolant level dropping, have the cooling system pressure‑tested immediately. Replacing a failing water pump preventatively is far cheaper than the overheating damage it can cause.

Weighing Your Options?

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840i - 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.

840i - 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?

ProblemRepairable?Typical CostWhen It Makes SenseNikasil liner degradation (M60)⚠️ Sometimes£3,000–£6,000Often requires full rebuild; assess overall engine healthTiming chain guides (M62)✅ Yes£1,500–£3,500Catch it early - before chain jumpsCoolant loss (B58)✅ Yes£400–£900Routine maintenance - do preventativelyPCV valve failure (B58)✅ Yes£400–£800Straightforward - replace valveSevere engine damage❌ Usually NoEngine replacementLittle left to salvage - replacement is the only option

Buying This 840i? Check These First

Buy If

E31 M60: Nikasil liners replaced or compression test passed
E31 M62: timing chain guides replaced or inspected
G14/G15/G16 B58: cooling system maintained with recent water pump work
Full service history with BMW-spec oil for the correct era

Avoid If

E31 M60: misfires or rough running - Nikasil may be degrading - walk away
E31 M62: cold‑start rattle - timing chain guides may be failing
G14/G15/G16 B58: coolant loss with no diagnosis - walk away
Engine warning light with no diagnosis - potentially expensive

Closing Verdict

The 840i badge is a journey through BMW grand touring history - from the classic E31 V8 to the modern G14/G15/G16 B58 straight‑six. The E31 M62 is the most reliable V8; the B58 is the most refined and reliable overall. The M60 is the most maintenance‑sensitive. Buy on generation‑specific history - and never ignore a cold‑start rattle or coolant loss.

Don't guess.Get the right engine at the right price.

→ Compare 840i engine prices before you buy

Don't Guess. Compare.

Get real quotes from vetted UK specialists and make the right call for your 320d.

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Buying Checklist

Before you buy a used BMW 8 Series 840i (or before you commit to an engine replacement), check these:

Cold Start

Listen for rattling (M62 timing chain guides)

Misfires (E31 M60)

Check for rough running; Nikasil liner degradation indicator

Coolant Level (B58)

Check for unexplained loss; water pump may be failing

Service History

including which generation (E31, G14/G15/G16 pre‑LCI or LCI) and confirmed maintenance

Oil Consumption

Does it use more than 1L per 1,000 miles?

PCV Valve (B58)

Check for rough idle; PCV failure indicator

Engine Warning Light

Have codes been read? Any unresolved issues?

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.

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.

M60B40 (4.0 V8)

Years1993–1996

Power286 hp (213 kW) @ 5,800 rpm; 400 Nm @ 4,500 rpm

2025 Enquiries- (pattern data)

Avg. Recon Cost£1,500–£3,500 [PLACEHOLDER]

Engine CodeYearsPower2025 EnquiriesAvg. Recon Cost

M60B40 (4.0 V8)1993–1996286 hp (213 kW) @ 5,800 rpm; 400 Nm @ 4,500 rpm- (pattern data)£1,500–£3,500 [PLACEHOLDER]

M62B44 (4.4 V8)1996–1999286 hp (213 kW) @ 5,700 rpm; 420 Nm @ 3,900 rpm- (pattern data)£2,000–£4,000 [PLACEHOLDER]

B58B30M1 (3.0 turbo I6)2018–2022333–340 hp (245–250 kW) @ 5,000–5,500 rpm; 500 Nm @ 1,600–4,500 rpm- (pattern data)£4,500–£7,500 [PLACEHOLDER]

B58B30C (3.0 turbo I6)2022–present333–340 hp (245–250 kW) @ 5,000–6,250 rpm; 500 Nm @ 1,700–4,000 rpm- (pattern data)£5,000–£8,500 [PLACEHOLDER]

Technical Specs

B58B30C 3.0 straight-six, G14/G15/G16 LCI

Displacement2,998 cc

Cylinders6-cylinder inline

Compression Ratio11.0:1

Fuel SystemDirect injection

TurbochargerTwin‑power turbo + 48V MHEV (select markets)

→ Compare 840i engine prices for your BMW

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Market Intelligence

Most Common Failure

E31 M60: Nikasil liner degradation; E31 M62: timing chain guides; B58: coolant system

[PATTERN DATA]

Average Enquiry Mileage

50,000

–80,000 miles

[PATTERN DATA]

Average Replacement Cost

£4,000

–£6,000 reconditioned, supply only

[PLACEHOLDER - confirm vs cost sheet]

Most Requested Engine Code

B58B30M1 / B58B30C

60%

of 840i enquiries

[PATTERN DATA]

Peak Enquiry Season

Summer

cooling issues exposed by warmer weather

[PATTERN DATA]

Regional Demand

South East18%

London16%

South West12%

PATTERN DATA

Regional Demand Breakdown

18%South East

16%London

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 code, 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.

Find the best BMW 8 Series 840i engine replacement UK drivers rely on. Compare prices from trusted specialists on EnginesMarket today and get back on the road with confidence - from £1,000 for a used unit to £8,500 for a fully rebuilt grand tourer engine.

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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