How much does a Mercedes C218 engine replacement cost in the UK?

A reconditioned C218 engine typically costs £2,500–£14,000 supply only, depending on engine — the volume CLS 250 CDI diesel sits at £2,500–£4,200. Fitting adds £650–£1,800. Use our calculator for a personalised figure.

What are the common problems with the Mercedes C218?

The OM642 V6 diesel suffers from oil cooler seal leaks (80k–150k miles). The OM651 four-cylinder diesel has injector seal failure ("Black Death"). The pre-facelift M276 V6 petrol has timing chain and cam adjuster wear. The M278 V8 (CLS 500) suffers from turbo coolant line and valve seal degradation. The CLS 63 AMG (M157) has high running costs and complex maintenance requirements.

Is the Mercedes C218 reliable?

It depends heavily on engine choice and maintenance history. The OM642 diesel is the most robust option; the OM651 is also solid. M276-engined cars (pre-2014) carry some timing chain risk — post-2014 facelift cars are improved. The M278 and M157 V8s are reliable for performance engines but have higher running costs and more complex maintenance. Always check service history and ensure oil changes were performed on schedule.

Which Mercedes C218 engine should I avoid?

The pre-facelift CLS 350 (M276.952) without documented timing chain history is one to approach with caution — chain and cam adjuster issues can occur from 60,000 miles. The CLS 63 AMG (M157) is a phenomenal car but running costs are substantial; avoid neglected examples without full service history. The CLS 500 (M278) is also costly to maintain; budget for turbo coolant line work.

How do I know if my C218 engine needs replacing?

Cold-start rattle (M276 timing chain), black carbon residue around injectors (OM651/OM642 diesel), blue smoke or coolant loss (M278/M157 V8s), or a sudden loss of power on any engine are the key warnings. Check engine lights, rough idle or misfires also warrant immediate inspection.

Is it worth replacing a Mercedes C218 engine, or should I scrap the car?

Depends on the car's value. Against a well-kept £16,000 C218, a £3,500–£6,000 recon is 22–38% of the car's value — a sensible repair. Against a tired £8,000 example, the same recon is 44–75% — marginal but sometimes worth it if the car is otherwise excellent. Our 70% Mercedes threshold is the line.

How long do Mercedes C218 engines last?

The OM642 V6 diesel can exceed 200,000 miles with proper servicing and oil cooler maintenance. The OM651 is similarly durable. The M276 V6 petrol can reach 150,000+ miles if the timing chain is addressed proactively. The M278 and M157 V8s can also reach high mileages but require more frequent maintenance and are more expensive to run. The C218's electronics and interior quality are generally robust.

What is the difference between the C218 and the X218 Shooting Brake?

The C218 is the four-door coupé (the iconic CLS shape). The X218 is the Shooting Brake estate variant, introduced in 2012. Both share the same platform, engines and mechanicals. The X218 offers significantly more load space and practicality but is rarer in the UK. Engine costs are identical; body-specific parts differ. See the X218 page for estate-specific costs.

How do I find my Mercedes C218 engine code?

Listed on the VIN plate (visible through the windscreen, lower passenger side), stamped on the engine block, and detailed in your vehicle registration documents (V5C). Tell us your variant (CLS 350 CDI, CLS 63 AMG, etc.) and approximate registration date, and we'll confirm it — 25+ vetted Mercedes specialists will verify it for free.

Mercedes CLS C218 Engines — The Complete UK Guide

Mercedes CLS C218 Engine Codes — The Complete Database

Every engine fitted to the second-generation CLS — from the four-cylinder diesel to the twin-turbo V8, including the facelift's 9G-Tronic updates.

Engine CodeFamilyFuelDisplacementPowerYears (C218)Variants (badges)Reliability2025 EnquiriesAvg. Recon Cost

OM651.924OM651Diesel I42.1L (2143cc)170 bhp (125 kW)2014–2018CLS 220 BlueTEC★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£2,500–£4,200 [MB-QUOTE]

OM651.924OM651Diesel I42.1L (2143cc)204 bhp (150 kW)2011–2018CLS 250 CDI / BlueTEC★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£2,500–£4,200 [MB-QUOTE]

OM642.852OM642Diesel V63.0L (2987cc)265 bhp (195 kW)2011–2014CLS 350 CDI★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

OM642.853OM642Diesel V63.0L (2987cc)265 bhp (195 kW)2013–2016CLS 350 BlueTEC★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

M276.952M276Petrol V63.5L (3498cc)306 bhp (225 kW)2011–2014CLS 350★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

M276.820M276Petrol V63.0L (2996cc)333 bhp (245 kW)2014–2018CLS 400★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

M278.922M278Petrol V84.7L (4663cc)408 bhp (300 kW)2011–2017CLS 500★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£5,000–£9,000 [MB-QUOTE]

M157.981M157Petrol V85.5L (5461cc)525–585 bhp (386–430 kW)2011–2017CLS 63 AMG★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£8,000–£14,000 [MB-QUOTE]

Engine CodeFuelPowerYearsReliabilityEnquiriesAvg. Recon Cost

OM651.924OM651Diesel I4170 bhp (125 kW)2014–2018★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£2,500–£4,200 [MB-QUOTE]

OM651.924OM651Diesel I4204 bhp (150 kW)2011–2018★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£2,500–£4,200 [MB-QUOTE]

OM642.852OM642Diesel V6265 bhp (195 kW)2011–2014★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

OM642.853OM642Diesel V6265 bhp (195 kW)2013–2016★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

M276.952M276Petrol V6306 bhp (225 kW)2011–2014★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

M276.820M276Petrol V6333 bhp (245 kW)2014–2018★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£3,500–£6,000 [MB-QUOTE]

M278.922M278Petrol V8408 bhp (300 kW)2011–2017★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£5,000–£9,000 [MB-QUOTE]

M157.981M157Petrol V8525–585 bhp (386–430 kW)2011–2017★★★★☆ [PROVISIONAL — pending dedicated Engine Page]— (pattern data)£8,000–£14,000 [MB-QUOTE]

Overview

Mercedes CLS C218 — Overview

The Mercedes-Benz CLS C218 — the second generation of the four-door coupé — launched at the 2010 Paris Motor Show.

Based on the W212 E-Class platform, the C218 brought a more aggressive design language, a new COMAND interface with touchpad, and the option of 4MATIC all-wheel drive for the first time. A significant facelift in 2014 introduced the 9G-Tronic transmission, updated engine options and revised styling. The C218 was produced until 2018, when it was replaced by the C257. The Shooting Brake (X218) estate variant was also offered from 2012.

Key Facts

Platform

Mercedes W212 (E-Class)

Predecessor

C219 (2004–2010)

Successor

C257 (2018–2023)

Sibling body styles in this generation

X218 Shooting Brake (estate)

Market Intelligence

No [MB-VERIFIED] enquiry data exists for the CLS C218 — the model is absent from EM_Proprietary_Data's per-model table, reflecting its lower-volume UK status compared to the E-Class and C-Class.

Mercedes CLS C218 — Overview

The Mercedes-Benz CLS C218 — the second generation of the four-door coupé — launched at the 2010 Paris Motor Show.

Based on the W212 E-Class platform, the C218 brought a more aggressive design language, a new COMAND interface with touchpad, and the option of 4MATIC all-wheel drive for the first time. A significant facelift in 2014 introduced the 9G-Tronic transmission, updated engine options and revised styling. The C218 was produced until 2018, when it was replaced by the C257. The Shooting Brake (X218) estate variant was also offered from 2012.

Key Facts

Platform

Mercedes W212 (E-Class)

Predecessor

C219 (2004–2010)

Successor

C257 (2018–2023)

Sibling body styles in this generation

X218 Shooting Brake (estate)

Market Intelligence

No [MB-VERIFIED] enquiry data exists for the CLS C218 — the model is absent from EM_Proprietary_Data's per-model table, reflecting its lower-volume UK status compared to the E-Class and C-Class.

Best & Worst Engines

Thin-Data Summary

“The CLS C218's engine range spans from efficient diesel to brutal AMG V8. For most buyers, the CLS 350 CDI / BlueTEC (OM642 V6 diesel) is the standout: smooth, refined and robust with few major failure modes beyond the well-documented oil cooler seal leak. The CLS 250 CDI (OM651) is the sensible diesel choice for most buyers: economical and well-supported. On the petrol side, the CLS 350 (M276 V6) offers a sweet-spot balance of performance and refinement, though early examples can suffer from timing chain and cam adjuster issues. The CLS 500 (M278 V8) delivers effortless V8 grunt, but the hot-vee design means higher running costs and potential turbo-related issues. The CLS 63 AMG (M157 V8) is a genuine performance icon — 525–585 bhp from a twin-turbo 5.5-litre V8 — but running costs are substantial and the engine is complex. Buying instruction: prioritise post-2014 facelift cars with the 9G-Tronic for better refinement; for long-term ownership, the OM642 diesel and M276 V6 petrol are the most reliable choices.”

Who it's for:

Thin-Data Summary

“The CLS C218's engine range spans from efficient diesel to brutal AMG V8. For most buyers, the CLS 350 CDI / BlueTEC (OM642 V6 diesel) is the standout: smooth, refined and robust with few major failure modes beyond the well-documented oil cooler seal leak. The CLS 250 CDI (OM651) is the sensible diesel choice for most buyers: economical and well-supported. On the petrol side, the CLS 350 (M276 V6) offers a sweet-spot balance of performance and refinement, though early examples can suffer from timing chain and cam adjuster issues. The CLS 500 (M278 V8) delivers effortless V8 grunt, but the hot-vee design means higher running costs and potential turbo-related issues. The CLS 63 AMG (M157 V8) is a genuine performance icon — 525–585 bhp from a twin-turbo 5.5-litre V8 — but running costs are substantial and the engine is complex. Buying instruction: prioritise post-2014 facelift cars with the 9G-Tronic for better refinement; for long-term ownership, the OM642 diesel and M276 V6 petrol are the most reliable choices.”

Who it's for:

Mercedes CLS C218 — Ownership Economics

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

OM651.924 (CLS 220/250 CDI)100k–150k+Injector seal failure£400–£1,000£2,500–£4,200

Solid diesel — economical and well-supported

OM642.852/853 (CLS 350 CDI)100k–180kOil cooler seal leak£800–£1,500£3,500–£6,000

Best diesel — smooth, refined, reliable

M276.952 (CLS 350)60k–120kTiming chain wear£800–£2,000£3,500–£6,000

Good V6 — balance of performance and reliability

M276.820 (CLS 400)60k–120kTiming chain wear (less common)£800–£2,000£3,500–£6,000

Improved — facelift V6, 9G-Tronic

M278.922 (CLS 500)60k–100kTurbo coolant lines, valve seals£1,500–£3,000£5,000–£9,000

V8 luxury — fast, but costly to maintain

M157.981 (CLS 63 AMG)50k–80kValve seals, turbo issues£2,000–£4,000£8,000–£14,000

Performance icon — AMG tax applies

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

OM651.924 (CLS 220/250 CDI)100k–150k+Injector seal failure£400–£1,000£2,500–£4,200

Solid diesel — economical and well-supported

OM642.852/853 (CLS 350 CDI)100k–180kOil cooler seal leak£800–£1,500£3,500–£6,000

Best diesel — smooth, refined, reliable

M276.952 (CLS 350)60k–120kTiming chain wear£800–£2,000£3,500–£6,000

Good V6 — balance of performance and reliability

M276.820 (CLS 400)60k–120kTiming chain wear (less common)£800–£2,000£3,500–£6,000

Improved — facelift V6, 9G-Tronic

M278.922 (CLS 500)60k–100kTurbo coolant lines, valve seals£1,500–£3,000£5,000–£9,000

V8 luxury — fast, but costly to maintain

M157.981 (CLS 63 AMG)50k–80kValve seals, turbo issues£2,000–£4,000£8,000–£14,000

Performance icon — AMG tax applies

The C218 rule

A £3,500–£6,000 CLS 350 CDI recon against a £8,000–£20,000 C218 sits at 18–75% of the car's value. On a sub-£10,000 example, that brushes our 70% Mercedes threshold — we'll honestly tell you to walk away. Against a well-kept £16,000+ example, the same recon drops to a more manageable 22–38% — a repair decision, not a financial one. Value the car first.

Key Takeaways

Which C218 Costs Least To Own?
CLS 250 CDI (OM651) — simple diesel, robust, cheap parts.
Which C218 Costs Most To Own?
CLS 63 AMG (M157) — twin-turbo V8 complexity, AMG-specific parts, high running costs.
Which C218 Is Best Value?
CLS 350 CDI (OM642) — the most reliable engine in the range with strong economy and refinement.

Common Problems

01

OM642

Oil Cooler Seal Leak

Affected models:

CLS 350 CDI / BlueTEC (OM642.852/853), 2011–2016.

Typical failure mileage:

80,000–150,000 miles.

Root cause:

The oil cooler seals on the OM642 V6 diesel are a known weak point. The seals degrade over time, allowing oil to leak into the valley of the V6. The repair is labour-intensive, requiring removal of the intake manifold and significant disassembly.

Tiered Cost Table

Our Recommendation

On any CLS 350 CDI over 80,000 miles, budget for an oil cooler seal replacement — £800–£1,500 is a reasonable preventative cost to avoid potential engine damage from oil loss.

Compare OM642 engine prices for your C218

02

OM651

Injector Seal Failure ("Black Death")

Affected models:

CLS 220/250 CDI (OM651.924), 2011–2018.

OM651 Injector Seal Failure ("Black Death")

Typical failure mileage:

80,000–130,000 miles.

Root cause:

The injector seals on the OM651 diesel engine degrade over time, allowing combustion gases to escape past the seal. This causes a characteristic black, tar-like carbon buildup around the injector — known in Mercedes circles as "Black Death" — which can eventually seize the injector in the cylinder head.

Tiered Cost Table

Our Recommendation

At the first sign of a diesel smell in the cabin or visible black residue around injectors, get the seals inspected immediately — a £400–£800 seal replacement is far cheaper than the £900–£1,500 head repair that follows if ignored.

Compare OM651 engine prices for your C218

03

M276

Timing Chain and Cam Adjuster Wear

Affected models:

CLS 350 (M276.952), 2011–2014.

Typical failure mileage:

60,000–120,000 miles.

Root cause:

The M276 V6 petrol engine family can suffer from premature timing chain stretch and wear to the camshaft adjuster sprockets. Cold-start rattling is the classic warning sign — if ignored, the chain can jump, causing piston-to-valve contact and catastrophic engine failure.

Tiered Cost Table

Our Recommendation

On any pre-facelift M276-engined C218 with no documented chain history, treat this as overdue preventative maintenance — an £800–£1,800 repair is dramatically cheaper than the £2,500–£4,500 replacement that follows if ignored. Post-2014 facelift cars with the M276.820 are less prone to this issue.

Compare M276 engine prices for your C218

04

M278

Hot-Vee V8 Turbo Coolant Leaks

Affected models:

CLS 500 (M278.922), 2011–2017.

Typical failure mileage:

60,000–100,000 miles.

Root cause:

The M278 twin-turbo V8's "hot-vee" design places the turbos inside the V of the engine, generating significant heat. This causes the turbo coolant lines and valve stem seals to degrade prematurely, leading to coolant leaks and oil consumption.

Tiered Cost Table

Our Recommendation

On any CLS 500, budget for a coolant system inspection at 60,000 miles — a £1,200–£2,000 preventative repair is cheaper than the £2,800–£5,000 rebuild that follows if ignored.

Compare M278 engine prices for your C218

C218 Engine Replacement Costs — By Engine and Condition

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

CLS 220 BlueTECOM651.924£1,200–£2,200£2,500–£4,200£3,500–£5,50010–12 hrs

CLS 250 CDI/BlueTECOM651.924£1,200–£2,200£2,500–£4,200£3,500–£5,50010–12 hrs

CLS 350 CDIOM642.852£1,800–£3,200£3,500–£6,000£5,000–£8,00012–14 hrs

CLS 350 BlueTECOM642.853£1,800–£3,200£3,500–£6,000£5,000–£8,00012–14 hrs

CLS 350M276.952£1,800–£3,200£3,500–£6,000£5,000–£8,00012–14 hrs

CLS 400M276.820£1,800–£3,200£3,500–£6,000£5,000–£8,00012–14 hrs

CLS 500M278.922£2,500–£4,500£5,000–£9,000£7,000–£12,00016–20 hrs

CLS 63 AMGM157.981£4,000–£7,000£8,000–£14,000£12,000–£18,00018–24 hrs

No Generation variance from the baseline figures — the C218 shares its engine bay layout with the W212 E-Class, so costs are consistent.

Core Variants

Diesel Variants

CLS 220 BlueTECCLS 250 CDICLS 250 BlueTECCLS 350 CDICLS 350 BlueTEC

Petrol Variants

CLS 350CLS 400CLS 500CLS 63 AMGCLS 63 AMG S-Model

Scope note: All variants listed are C218 (four-door coupé, 2011–2018) only. The X218 Shooting Brake (estate) shares the same engines but is covered on a separate Generation Page per the one-page-per-body-code rule. The CLS 400 replaced the CLS 350 post-facelift (2014). The CLS 63 AMG S-Model (585 bhp) was introduced post-facelift.

Core Variants

Diesel Variants

CLS 220 BlueTECCLS 250 CDICLS 250 BlueTECCLS 350 CDICLS 350 BlueTEC

Petrol Variants

CLS 350CLS 400CLS 500CLS 63 AMGCLS 63 AMG S-Model

Scope note: All variants listed are C218 (four-door coupé, 2011–2018) only. The X218 Shooting Brake (estate) shares the same engines but is covered on a separate Generation Page per the one-page-per-body-code rule. The CLS 400 replaced the CLS 350 post-facelift (2014). The CLS 63 AMG S-Model (585 bhp) was introduced post-facelift.

Market Intelligence

Most Requested E90 Engines (2025)

Most Requested E90 Variants

Average E90 Replacement Cost

Most Common E90 Failures

FAQ

BMW 3 Series E90 rear three-quarter view

Why UK Mercedes CLS C218 Owners Trust MercedesEngines.uk

Trusted C218 Engine Suppliers
every garage and engine rebuilder in our network is vetted, rated and reviewed by real CLS owners, as part of the Engine Finders network.
Compare C218 Engine Replacement Companies
see prices, warranty terms and supply-and-fit options side-by-side before you commit to any repair.
UK Engine Replacement Services for C218
covering every variant from the CLS 250 CDI to the CLS 63 AMG, with supply-only or full supply-and-fit available nationwide.

Find the best Mercedes CLS C218 engine replacement UK drivers rely on. Compare real prices from trusted Mercedes specialists on EnginesMarket today and get back on the road with confidence.

Compare Mercedes CLS C218 Engine Prices on EnginesMarket

Why UK Mercedes CLS C218 Owners Trust MercedesEngines.uk

Trusted C218 Engine Suppliers
every garage and engine rebuilder in our network is vetted, rated and reviewed by real CLS owners, as part of the Engine Finders network.
Compare C218 Engine Replacement Companies
see prices, warranty terms and supply-and-fit options side-by-side before you commit to any repair.
UK Engine Replacement Services for C218
covering every variant from the CLS 250 CDI to the CLS 63 AMG, with supply-only or full supply-and-fit available nationwide.

Find the best Mercedes CLS C218 engine replacement UK drivers rely on. Compare real prices from trusted Mercedes specialists on EnginesMarket today and get back on the road with confidence.

Compare Mercedes CLS C218 Engine Prices on EnginesMarket