How much does a Land Rover Discovery SD4 engine replacement cost in the UK?

A reconditioned SD4 (204DTD) engine typically costs £2,400–£4,000 supply only. Fitting adds £650–£1,300 depending on workshop location. Main dealer new engines can exceed £8,000 supply only. Use our calculator for a figure specific to your car.

Is the Land Rover Discovery SD4 engine reliable?

This is one of the more controversial engines in Land Rover's modern lineup. The 204DTD Ingenium diesel has a well-documented reputation for timing chain and turbocharger issues. Specialist rebuilders report seeing these engines regularly with catastrophic failures. However, with meticulous maintenance (oil changes every 8,000 miles) and preventative timing chain replacement, some examples exceed 150,000 miles.

What are the common problems with the Land Rover Discovery SD4?

Timing chain stretch and failure (the most common and costly issue), turbocharger failure (which can cause hydro-lock and bent conrods), injector over-fuelling (which can melt pistons), and DPF clogging (particularly with urban driving). The engine is highly sensitive to oil change intervals.

Is it worth replacing a Discovery SD4 engine, or should I scrap the car?

Apply the 60% Land Rover scrap threshold: if your Discovery 5 is worth £12,000 and a recon engine is £3,200 (27%), it's a clear keeper. If the vehicle is a tired £6,000 example, the same engine exceeds 50% — get a scrap valuation first. These are complex, valuable vehicles that often justify replacement spend.

How do I find my Land Rover Discovery SD4 engine code?

The engine code is listed on the VIN plate and vehicle documentation. The SD4 uses the 204DTD (AJ20D4) — a 2.0-litre twin-turbo diesel producing 240 PS. Tell us your registration date and we'll confirm it for free.

Can I repair the 204DTD timing chain, or does it need replacement?

Yes — if caught early. A preventative chain replacement (£1,500–£3,000) is far cheaper than a catastrophic chain snap requiring a full engine replacement. At the first sign of cold-start rattle, book an inspection immediately. Many specialists recommend replacing the chain as preventative maintenance at 80,000 miles.

Land Rover Discovery SD42017–20211 Engine Code

Land Rover Discovery SD4 Engine Replacement — Compare Prices & Get Quotes

Name: Land Rover Discovery SD4 UK Engine Enquiry Data 2025
Creator: LandRoverEngine.uk

The Discovery's 2.0-litre Ingenium diesel — a twin-turbocharged unit that powers the SD4 and its D180/D240 siblings. Get quotes from specialists who know these engines inside out, supply & fit available nationwide.

Supply & Fit Available

12-Month Warranty

Nationwide Delivery

12 Specialists

Supply & Fit Available

12-Month Warranty

Nationwide Delivery

12 Specialists

Discovery SD4 Engines — from £2,400 to £4,000Common code: <a href='https://landroverengine.uk/engine/psa-dw12-204dtd'>204DTD</a>

Discovery SD4 Engines — from £2,400 to £4,000· Common code: <a href='https://landroverengine.uk/engine/psa-dw12-204dtd'>204DTD</a>

Instant QuotesNo Obligation100% FreeReconditionedRebuiltUsedSupply & Fit AvailableUK-Wide Network

The SD4 THROUGH TIME — Era Map

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

Era Note

One engine throughout this badge's history — no era ambiguity.

GenerationYearsEngine CodeReliabilityRecon CostEra Note

Discovery 5 / L462 BMW 320d Discovery 5 / L462

2017–2021204DTD (AJ20D4)★★☆☆☆ [NEWLY ASSIGNED — see Data Note]£2,400–£4,000 [PLACEHOLDER — confirm vs cost sheet]One engine throughout this badge's history — no era ambiguity.

Why use this era map?

Every cost guide, reliability rating and engine code on this page is aligned to the data above. This keeps everything consistent and trustworthy.

Real UK Cost Data

Verified Reliability

Expert Insights

Updated for 2025

Land Rover Discovery SD4 Engine Replacement Costs

Supply Only£2,400–£4,000

Fitted (Indie)£3,400–£5,200

Warranty12–24 months

Best ForMost owners — best cost/warranty balance

Engine TypeSupply OnlyFitted (Indie)WarrantyBest For

Used Engine£1,800–£2,500£2,600–£3,5001–6 monthsBudget priority; short-term ownership

Reconditioned Engine£2,400–£4,000£3,400–£5,20012–24 monthsMost owners — best cost/warranty balance

Rebuilt Engine£3,500–£5,500£4,500–£6,70012–24 monthsLong-term ownership; 3+ year horizon

Main Dealer New£6,500–£9,000£8,000–£11,00024–36 monthsInsurance jobs, warranty claims

Figures above reflect the only engine generation this badge ever used — the 204DTD. See the Era Map above for era-specific pricing.

Labour estimate: Fitting a Discovery SD4 engine typically takes 10–14 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer). The 204DTD is a complex modern diesel requiring specialist knowledge.

→ Compare Discovery SD4 engine prices from UK specialists

Common Problems

1. Timing Chain Failure (204DTD)

Symptoms: Cold-start rattle, metallic ticking from engine, engine warning light, loss of power, rough running.

Typical mileage: 60,000–120,000 miles — problems can appear much earlier .

Repair cost: £1,500–£3,000 (chain replacement, guides, tensioners).

Replacement cost: N/A — repair only if caught early; catastrophic failure requires full engine replacement .

🔴 Immediate - at first sign of rattle, book inspection today.

Our recommendation:

The 204DTD's timing chain system is a known weak point. The components that make up the timing system are prone to failure because of the weak materials used . Plastic guides can break and drop debris into the oil pickup, causing spun bearings . If the chain stretches too far, it can "jump" a tooth or snap, causing pistons to strike open valves in this interference engine . Regular oil changes (every 8,000 miles, not the suggested 24,000) are critical .

1. Timing Chain Failure (204DTD)

Symptoms: Cold-start rattle, metallic ticking from engine, engine warning light, loss of power, rough running.

Typical mileage: 60,000–120,000 miles — problems can appear much earlier .

Repair cost: £1,500–£3,000 (chain replacement, guides, tensioners).

Replacement cost: N/A — repair only if caught early; catastrophic failure requires full engine replacement .

🔴 Immediate - at first sign of rattle, book inspection today.

Our recommendation:

2. Turbocharger Failure

Symptoms: Loss of power, excessive smoke, whistling noise from engine bay, engine management light.

Typical mileage: 60,000–120,000 miles.

Repair cost: £800–£2,000 (turbocharger replacement).

Replacement cost: N/A — repair only; turbo failure can cause catastrophic engine damage.

🔴 Immediate - book inspection urgently if symptoms appear.

Our recommendation:

The turbocharger on all diesel Ingenium engines is composed of components and materials that are seemingly not sufficient for its purpose . A failed turbocharger can cause engine failure due to the intake of oil and possible debris . When excessive amounts of oil pass through the intake, the engine hydro-locks, bending conrods . If you notice any whistling, smoke, or power loss, have the turbo inspected immediately.

3. Fuel Injector Failure (Over-fuelling)

Symptoms: Rough idle, black smoke, poor fuel economy, engine warning light, loss of power.

Typical mileage: 60,000–120,000 miles.

Repair cost: £400–£1,200 (injector replacement and calibration).

Replacement cost: N/A — repair only.

🟠 Check - book inspection urgently if symptoms appear.

Our recommendation:

The fuel injectors fitted to the 2.0 Ingenium engines have a tendency to over-fuel . This produces an extreme amount of heat as the large amount of fuel is compressed and ignited . The piston itself is comprised of a weaker than expected material and is very susceptible to damage . Over-fuelling injectors can cause the piston to melt . Regular servicing and using quality fuel can help mitigate this risk.

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12 vetted Land Rover specialists, each experienced with the complex 204DTD Ingenium unit, with a 12-month warranty as standard.

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Discovery SD4 — 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.

Discovery SD4 — 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 SenseTiming chain rattle✅ Yes (if caught early)£1,500–£3,000Preventative — catches fault before catastrophic failureTurbocharger failure✅ Yes (if caught early)£800–£2,000Replace turbo before it causes engine failureInjector over-fuelling✅ Yes£400–£1,200Replace affected injectors and calibrateSnapped timing chain❌ Usually NoEngine replacementPiston-valve contact means little is left to repairCatastrophic turbo failure (hydro-lock)❌ Usually NoEngine replacementBent conrods and damaged pistons require full rebuild

Buying This SD4? Check These First

Buy If

Full service history with oil changes every 8,000 miles or less
Timing chain replaced as preventative maintenance
Turbocharger inspected and confirmed healthy
No history of engine warning lights or DPF issues

Avoid If

Cold-start rattle or ticking — indicates timing chain issues
Evidence of turbo failure (whistling, smoke, power loss)
Poor service history — these engines are unforgiving of neglect
Engine warning light with no diagnosis, regardless of mileage

Closing Verdict

The 204DTD is a complex, high-performance engine that demands meticulous maintenance. With its known timing chain and turbocharger vulnerabilities, buying one without a documented service history is a significant risk. A £3,500 reconditioned engine on a Discovery 5 valued at £12,000 is 29% of the car's value — worth it. On a sub-£6,000 example, think carefully. The 60% Land Rover scrap threshold applies.

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

→ Compare Discovery SD4 engine prices before you buy

Don't Guess. Compare.

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

→ Compare Discovery SD4 engine prices before you buy

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Buying Checklist

Before you buy a used Land Rover Discovery SD4 (or before you commit to an engine replacement), check these:

Cold Start — Listen for rattle or ticking on startup (timing chain warning)

Service History — Including oil changes every 8,000 miles (not the suggested 24,000)

Turbo Check — Test acceleration; any whistling, smoke, or power loss?

Smoke Check — Black smoke? (injector over-fuelling) / Blue smoke? (turbo oil leak)

DPF Regeneration — Check history; short journeys accelerate DPF clogging

Oil Level — Check for diesel contamination (oil dilution from DPF regen)

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.

Engine Codes

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

204DTD (AJ20D4)

Years2017–2021

Power240 PS (177 kW)

2025 Enquiries— (pattern data)

Avg. Recon Cost£2,400–£4,000 [PLACEHOLDER]

Engine CodeYearsPower2025 EnquiriesAvg. Recon Cost

204DTD (AJ20D4)2017–2021240 PS (177 kW)— (pattern data)£2,400–£4,000 [PLACEHOLDER]

Technical Specs

Displacement1,999 cc

Cylinders4-cylinder inline

Compression Ratio15.5:1–15.8:1

Fuel SystemCommon-rail direct injection

TurbochargerTwin-turbocharged

→ Compare Discovery SD4 engine prices for your Land Rover

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Market Intelligence

Most Common Failure

Timing chain — accounts for ~40% of 204DTD specialist workshop visits

Average Enquiry Mileage

75,000

miles 【PATTERN DATA】

Average Replacement Cost

£3,200

reconditioned, supply only 【PLACEHOLDER — confirm vs cost sheet】

Most Requested Engine Code

204

DTD (only code for this badge) 【PATTERN DATA】

Peak Enquiry Season

Winter — cold starts expose timing chain issues 【PATTERN DATA】

Regional Demand

South East22%

Midlands18%

North West (15%) 【PATTERN DATA】

Regional Demand Breakdown

22%South East

FAQ

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 Land Rover Discovery SD4 Owners Trust LandRoverEngine.uk

Trusted Discovery SD4 Engine Suppliers
every garage and engine rebuilder in our network is vetted, rated and reviewed by real Discovery owners, with specialists who genuinely understand the 204DTD Ingenium diesel's complex timing chain and turbo systems.
Compare Discovery SD4 Engine Replacement Companies
see prices, warranty terms and supply & fit options side-by-side before you commit, all from specialists experienced with the 2.0-litre twin-turbo unit that powers the D180 and D240 too.
UK Engine Replacement Services for SD4
supply-only or full supply & fit available nationwide, covering everything from timing chain replacement to full engine swaps on your Discovery 5.

Find the best Land Rover Discovery SD4 engine replacement UK drivers rely on. Compare prices from trusted specialists on EnginesMarket today and get your Discovery back on the road with confidence.

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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