BMW 3 Series M340d2020–presentB57D30T2

BMW 3 Series M340d Engine Replacement —Compare Prices &
Get Quotes

Name: BMW 3 Series M340d UK Engine Enquiry Data 2025
Creator: BMWEngines.uk

The M340d packs BMW's most potent straight-six diesel — the B57D30T2 with 340 bhp and 700 Nm of torque, paired with xDrive and 48V mild-hybrid technology. Get quotes from trusted UK specialists today.

Supply &Fit Available
12-MonthWarranty
NationwideDelivery
20+Specialists

Supply &Fit Available
12-MonthWarranty
NationwideDelivery
20+Specialists

3 Series M340d Engines — from £3,000 to £8,500B57D30T2

Instant Quotes
No Obligation
100% Free
Reconditioned
Rebuilt
Used
Supply & Fit Available
UK-Wide Network

Instant Quotes
No Obligation
100% Free
Reconditioned
Rebuilt
Used
Supply & Fit Available
UK-Wide Network

BMW 3 Series M340d Engine Replacement Costs

Supply Only£5,000 – £7,500
Fitted (Indie)£6,300 – £8,900
Warranty12–24 months
Best ForMost owners — best cost/warranty balance

Engine Type	Supply Only	Fitted (Indie)	Warranty	Best For
Used Engine	£3,000 – £4,500	£4,200 – £5,900	1–6 months	Budget priority; lower-mileage donor
Reconditioned Engine	£5,000 – £7,500	£6,300 – £8,900	12–24 months	Most owners — best cost/warranty balance
Rebuilt Engine	£6,000 – £8,500	£7,300 – £9,900	12–24 months	Long-term ownership; 3+ year horizon
Main Dealer New	£8,500 – £12,000	£9,800 – £13,500	24–36 months	Insurance jobs, warranty claims

Figures above reflect the current B57D30T2 generation; LCI-era pricing runs slightly higher — see the Era Map above.

Labour estimate: Fitting a 3 Series M340d engine typically takes 12–16 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer).

Compare M340d engine prices from UK specialists

Common Problems With BMW 3 Series M340d Engines

1. DPF Clogging(Short Journey Use)

Symptoms: DPF warning light, reduced engine performance, increased fuel consumption, engine entering limp mode.
Typical Mileage: 30,000–80,000 miles (depends on usage pattern)
Repair Cost: £300–£800 (forced regeneration or DPF clean) / £1,500–£3,000 (DPF replacement) [PLACEHOLDER — confirm vs cost sheet]
Replacement Cost: N/A — repair only (unless DPF is physically damaged)
Urgency: Monitor — book inspection soon

Our recommendation:

Like all modern diesels, the B57 needs regular long runs for passive DPF regeneration. If your M340d is used primarily for short journeys, plan a 30–45 minute motorway run every two weeks. If the DPF warning light comes on, book a forced regeneration promptly — ignoring it can lead to costly DPF replacement.

1. DPF Clogging(Short Journey Use)

Symptoms: DPF warning light, reduced engine performance, increased fuel consumption, engine entering limp mode.
Typical Mileage: 30,000–80,000 miles (depends on usage pattern)
Repair Cost: £300–£800 (forced regeneration or DPF clean) / £1,500–£3,000 (DPF replacement) [PLACEHOLDER — confirm vs cost sheet]
Replacement Cost: N/A — repair only (unless DPF is physically damaged)
Urgency: Monitor — book inspection soon

Our recommendation:

2. EGR Valve and Cooler Carbon Build-up

Symptoms: Rough idling, reduced engine performance, increased fuel consumption, coolant loss (if cooler fails), engine warning light.
Typical Mileage: 40,000–80,000 miles
Repair Cost: £400–£1,000 (EGR cleaning or replacement) [PLACEHOLDER — confirm vs cost sheet]
Replacement Cost: N/A — repair only
Urgency: Monitor — book inspection soon

Our recommendation:

The EGR system on the B57 can become clogged with carbon deposits over time. Regular servicing and occasional Italian tune-ups can help. If you notice rough running or a drop in performance, have the EGR system inspected — cleaning it is far cheaper than replacing a failed EGR cooler.

3. Turbocharger Wastegate Actuator Wear

Symptoms: Rattling noise from the engine at low speeds or idle, noticeable drop in power, boost pressure loss.
Typical Mileage: 60,000–100,000 miles
Repair Cost: £800–£1,500 (wastegate actuator replacement) [PLACEHOLDER — confirm vs cost sheet]
Replacement Cost: N/A — repair only (if caught before turbo damage)
Urgency: Check — book inspection urgently if rattling or power loss occurs

Our recommendation:

The B57's twin-turbo setup delivers exceptional performance, but the wastegate actuator can wear over time. If you hear a rattling noise from the engine bay or notice a drop in power, have the turbo system inspected. Replacing a worn actuator is far cheaper than a full turbo replacement.

Ready to Compare?

Get Matched With a Vetted BMW Specialist

20+ vetted BMW specialists, every M340d engine covered, with a 12‑month warranty as standard.

Get My Free M340d Engine Quotes Now

M340d — Repair, Buy, or Replace?

Not every issue means a new engine.Here’s what can be repaired, when it makes sense, and what to check before you buy.

Can It Be Repaired?

Problem	Repairable?	Typical Cost	When It Makes Sense
DPF clogging	Yes	£300 – £800	Routine maintenance — forced regen or clean
EGR carbon build-up	Yes	£400 – £1,000	Routine maintenance — clean or replace valve
Wastegate actuator wear	Yes	£800 – £1,500	Catch it early — before turbo damage
AdBlue system faults	Yes	£500 – £1,500	Often software — can be resolved; hardware faults require specialist
Severe engine damage (timing chain / overheating)	Usually No	Engine replacement	Little left to salvage — replacement is the only option

ProblemRepairable? · Typical Cost

DPF clogging

Yes£300 – £800

Routine maintenance — forced regen or clean

EGR carbon build-up

Yes£400 – £1,000

Routine maintenance — clean or replace valve

Wastegate actuator wear

Yes£800 – £1,500

Catch it early — before turbo damage

AdBlue system faults

Yes£500 – £1,500

Often software — can be resolved; hardware faults require specialist

Severe engine damage (timing chain / overheating)

Usually NoEngine replacement

Little left to salvage — replacement is the only option

Buying This M340d? Check These First

Buy if:

Documented DPF regeneration history or regular long-distance driving
EGR system cleaned or replaced within the last 40,000 miles
No rattling from the turbo area — wastegate actuator in good condition
Full BMW service history with correct oil spec

Avoid if:

DPF warning light with no regeneration history — may indicate heavy clogging
Rough idle with no EGR history — carbon build-up may be significant
Rattling from the engine bay — wastegate actuator may be failing
Engine warning light with no diagnosis — potentially expensive emissions system issues

Closing verdict

The B57 is one of BMW's finest modern diesel engines — a 3.0-litre straight-six with 340 bhp, 700 Nm and genuine M‑lite performance. It's not without its watchpoints — DPF, EGR, wastegate actuator and AdBlue are the main areas to monitor — but it's fundamentally robust. Buy on full service history and pay attention to DPF health. A well‑maintained M340d is a long‑lived performance diesel.

Don’t Guess. Compare.

Get real quotes from vetted UK specialists and make the right call for your 3 Series M340d.

Compare M340d engine prices before you buy

20+ Vetted SpecialistsUK Network
12-Month Warrantyas Standard
Nationwide Delivery& Collection
Transparent PricingNo Hidden Fees
Thousands of 3 Series M340dOwners Helped

Buying Checklist

Before you buy a used BMW 3 Series M340d (or before you commit to an engine replacement), check these:

1. DPF Status
Check for warning lights; short journeys can cause clogging
2. Cold Start
Listen for rattling; wastegate actuator wear indicator
3. Rough Idle
Check for uneven running; EGR carbon build-up possible
4. Service History
Including which generation (pre‑LCI or LCI) and confirmed maintenance
5. Coolant Level
Check for unexplained loss; EGR cooler or water pump may be failing
6. AdBlue System
Check for warning lights; AdBlue system faults are common
7. Oil Consumption
Does it use more than 1L per 1,000 miles?
8. MOT History
Check for emissions‑related failures

Why this matters

A 10-minute check now can save you thousands later. The right 3 Series M340d is a superb long-term car — the wrong one can be expensive fast.

Buying Checklist

Before you buy a used BMW 3 Series M340d (or before you commit to an engine replacement), check these:

1
DPF Status
Check for warning lights; short journeys can cause clogging
2
Cold Start
Listen for rattling; wastegate actuator wear indicator
3
Rough Idle
Check for uneven running; EGR carbon build-up possible
4
Service History
Including which generation (pre‑LCI or LCI) and confirmed maintenance
5
Coolant Level
Check for unexplained loss; EGR cooler or water pump may be failing
6
AdBlue System
Check for warning lights; AdBlue system faults are common
7
Oil Consumption
Does it use more than 1L per 1,000 miles?
8
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 3 Series M340d pitfalls.

Engine Codes

This table's rows match Section 1B's Era Map exactly.

B57D30T2 (3.0 straight-six twin-turbo)

Years: 2020–2022
Power: 340 bhp @ 4,400 rpm; 700 Nm @ 1,750–2,250 rpm
2025 Enquiries: —(pattern data)
Avg. Recon Cost: £5,000–£7,500[PLACEHOLDER]

Engine Code	Years	Power	2025 Enquiries	Avg. Recon Cost
B57D30T2 (3.0 straight-six twin-turbo)	2020–2022	340 bhp @ 4,400 rpm; 700 Nm @ 1,750–2,250 rpm	—(pattern data)	£5,000–£7,500[PLACEHOLDER]
B57D30T2 (3.0 straight-six twin-turbo, 48V MHEV)	2022–present	340 bhp @ 4,400 rpm; 700 Nm @ 1,750–2,250 rpm + 19 bhp e‑boost	—(pattern data)	£5,500–£8,000[PLACEHOLDER]

Technical SpecsB57D30T2 3.0 straight-six diesel

Displacement: 2,993 cc
Cylinders: 6-cylinder inline
Compression Ratio: 16.5:1
Fuel System: Common-rail direct injection
Turbocharger: Twin-turbo (Bi-Turbo)

Compare M340d engine prices for your BMWGet quotes from trusted UK specialists in minutes.

Market Intelligence

Real data from thousands of 3 Series M340d enquiries in 2025.

Most Common FailureDPF clogging / EGR carbon build-up

The most frequently reported B57 issues

Average Enquiry Mileage

45,000–65,000

miles

[PATTERN DATA]

Average Replacement Cost

£6,000

reconditioned, supply only

[PLACEHOLDER]

Most Requested Engine Code

B57D30T2

[PATTERN DATA]

Peak Enquiry Season

Autumn/Winter

DPF and AdBlue issues exposed by colder weather

Regional Demand

South East: 19%
London: 17%
North West: 13%
Other Regions: 51%

[PATTERN DATA]

Regional Demand Breakdown

17%London19%South East13%North West51%Other Regions

Frequently Asked Questions

A reconditioned B57D30T2 engine typically costs £5,000–£7,500 supply only, with LCI-era MHEV units slightly higher. Fitting adds £1,200–£1,700. Use our calculator for a figure specific to your M340d.

Yes — the B57 is a modern, well‑engineered straight‑six diesel. It's significantly more reliable than earlier BMW diesels like the N47. The main watchpoints are DPF clogging, EGR carbon build-up, wastegate actuator wear, and AdBlue system faults — all manageable with proper maintenance.

DPF clogging (short journey use), EGR valve and cooler carbon build-up, turbocharger wastegate actuator wear, AdBlue system faults, and coolant loss. The engine itself is fundamentally robust.

Depends on vehicle value. A G20 M340d is a £25,000–£45,000 vehicle — a £6,000 recon is 13–24% of the car's value, making replacement a clear decision. This is well within our 70% BMW scrap threshold.

Listed on the VIN plate and vehicle documentation. The M340d engine code is B57D30T2 — a 3.0-litre straight-six twin-turbo diesel. Tell us your registration date and we'll confirm it for free.

Yes — regular long runs for DPF health, periodic EGR cleaning, and BMW-spec oil changes with shortened intervals (5,000–7,500 miles) are the most effective prevention. If you notice rattling or a drop in power, have the turbo system inspected immediately.

Disclaimer: 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.

Why UK BMW 3 Series M340d Owners Trust BMWEngines.uk

Find the best BMW 3 Series M340d engine replacement UK drivers rely on.

Compare prices from trusted specialists on EnginesMarket today and get back on the road with confidence — from £3,000 for a used unit to £8,500 for a fully rebuilt performance diesel.

Compare BMW 3 Series M340d Engine Prices Now

100% FreeNo hidden fees
No ObligationGet quotes with zero pressure
UK Specialists20+ vetted experts
12-Month WarrantyAs standard
Nationwide DeliverySupply & fit available

BMW 3 Series M340d Engine Replacement —Compare Prices &Get Quotes

BMW 3 Series M340d Engine Replacement Costs

Common Problems With BMW 3 Series M340d Engines

1. DPF Clogging(Short Journey Use)

2. EGR Valve and Cooler Carbon Build-up

3. Turbocharger Wastegate Actuator Wear

1. DPF Clogging(Short Journey Use)

2. EGR Valve and Cooler Carbon Build-up

3. Turbocharger Wastegate Actuator Wear

Ready to Compare?

M340d — Repair, Buy, or Replace?

Can It Be Repaired?

Buying This M340d? Check These First

Buying Checklist

Buying Checklist

Engine Codes

Market Intelligence

Regional Demand Breakdown

Frequently Asked Questions

Why UK BMW 3 Series M340d Owners Trust BMWEngines.uk

BMW 3 Series M340d Engine Replacement —Compare Prices &
Get Quotes