Range Rover 306DT/508PS/368DT Specialist Engine ReplacementCompare Quotes

A rebuilt 3.0L TDV6/SDV6 costs £4,500-£7,800 supply & fitted. The 4.4L SDV8 runs £5,000-£8,500, while the 5.0L supercharged V8 (AJ133) costs £6,000-£11,000. Used engines start lower but carry higher risk.

• Full rebuilt engine supply & fit: £4,500-£11,000 depending on engine code
• Used engine supply only: £1,500-£4,500 - but warranty limited or none
• Reconditioned units average £3,200-£7,500 with 12-month warranty
• Fitting alone adds £600-£1,200 to any engine price
• SDV6 timing chain replacement is £900-£1,600 - much cheaper than full failure

The 4.4L BMW M62 V8 (2002-2005) and naturally aspirated 5.0L AJ V8 are the most dependable. The newer 3.0L Ingenium straight-six MHEV shows strong early reliability, while the 4.4L SDV8 is the safest diesel bet.

• BMW 4.4L M62 V8 - widely regarded as one of the strongest Range Rover engines ever fitted
• Naturally aspirated 5.0L AJ V8 - more reliable than supercharged version, runs cooler
• 4.4L SDV8 diesel - lower failure rate than TDV6, excellent torque delivery
• 3.0L Ingenium inline-six MHEV - excellent early reliability, avoid four-cylinder Ingenium

The 3.0L TDV6 (306DT) has a Ford-derived bottom-end design flaw causing a 2-3% crankshaft failure rate regardless of service history. Failure is sudden and often catastrophic.

• TDV6 crankshaft failure hits 2-3% of units - independent of maintenance
• Catastrophic failure often occurs between 70,000-110,000 miles with no warning
• SDV6 has lower 1% failure rate than standard TDV6
• Once crank seizes, full replacement is only option - regrind rarely possible
• Early warning sign is bottom-end knock - stop driving immediately

Research data shows 68% of SDV6 units reach 150,000 miles with proactive timing chain and EGR intervention. Only 41% of TDV6 units hit 150k due to crankshaft and timing chain design flaws.

• SDV6 (3.0L diesel): 68% reach 150,000 miles with proper maintenance
• TDV6 (3.0L diesel): Only 41% reach 150,000 miles - avoid high-mileage examples
• Timing chain service at 100k (TDV6) or 112k (SDV6) is non-negotiable
• EGR cooler fails on 68% of units between 90,000-130,000 miles
• Crankshaft failure independent of maintenance - purely design flaw

A metallic rattle on cold start is the earliest sign. Left unchecked, the engine throws camshaft correlation codes (P0017/P0018), then misfires, loses power, and eventually jumps timing - destroying valves and pistons.

• Brief metallic rattle or chatter on cold start - first warning sign
• Check engine light with P0017-P0019 codes - cam/crank correlation mismatch
• Rough idle, hesitation, loss of power as timing drifts out of specification
• Deferring chain service risks piston-to-valve collision - catastrophic damage
• Preventative replacement at 100-112k miles costs £900-£1,600 vs £5k+ for new engine

The AJ133 is a charismatic, powerful engine but has two well-documented weak points: coolant crossover pipes (plastic, fail every 4-5 years) and timing chain tensioners. Frequent oil changes (5,000-7,500 miles) prevent timing issues.

• Plastic coolant crossover pipes fail every 50,000-70,000 miles - sudden coolant loss risk
• Replace cooling system proactively at 60k miles - specialist cost £900-£1,600
• Frequent oil changes (5,000-7,500 miles) prevent timing chain tensioner failure
• Aftermarket metal coolant lines available as permanent fix
• Supercharger coupler rattle at idle is common - snout rebuild costs £650-£1,100

Rebuild only for minor failures (top end, gaskets, EGR) below £2,500. For timing chain jump, crankshaft failure, or seized engine, replacement is cheaper and comes with warranty. Full rebuild on a TDV6 costs nearly as much as a warranted replacement.

• Light rebuild (gaskets, EGR, ancillaries): £2,500-£3,500 - often worth it
• Full rebuild after major failure: £4,000-£6,000 - approaches replacement cost
• Replacement with warranted rebuilt unit: £4,500-£7,800 - new engine, same price
• Replaced engines include 12-month warranty - rebuilds often don't
• For TDV6 with bottom end damage: replacement is only sensible option

Diesel SDV6 achieves 34-38 mpg officially, 35 mpg real-world. Petrol V8s return 23.5-29 mpg. The modern 3.0L MHEV petrol manages around 25 mpg. PHEV offers 40-50 miles electric range then 31 mpg.

• 3.0L SDV6 diesel: 34-38 mpg official, 35 mpg real-world, 40+ mpg on motorway runs
• 5.0L supercharged V8: 23.5-29 mpg official - expect low 20s in real use
• 4.4L SDV8 diesel: around 32-35 mpg depending on driving
• P400e PHEV: 40-50 miles electric range, then approximately 31 mpg

Check your V5C logbook under 'Vehicle details' for the engine number. The code is the first 4-6 characters (e.g., 306DT). Alternatively, open the driver's door and check the chassis plate or use our registration lookup above for instant identification.

• V5C registration document (logbook) - 'Engine number' field shows the code
• Driver's door chassis plate - engine code on VIN sticker
• Service history documents - engine type recorded at each service
• Under-bonnet compliance sticker - near front crossmember on L405
• Use registration lookup above - instant engine code identification

If the body and chassis are solid and the vehicle is otherwise well-maintained, a warranted replacement engine at £4,500-£7,800 is often better value than a used replacement car with unknown history. On a 2006-2009 L322, replacement may exceed vehicle value.

• L405 (2012-2021) worth £12k-£25k - replacement engines are good value
• L322 (2002-2012) worth £4k-£10k - replacement only viable for clean examples
• Replacement engine comes with 12-month unlimited mileage warranty
• A used replacement car has unknown service history - same engine risks
• If body, gearbox, suspension are sound - replacement makes financial sense