

Mercedes CLS 320Engine Rebuild— From £2,800
Specialist Mercedes CLS 320 engine rebuilds and replacements, with registration-based engine matching, nationwide recovery and a 12-month unlimited-mileage warranty
Rated Mercedes Engine Specialists — 1,800+ Engines Rebuilt
Specialist technicians with 10-15 years of experience
12 Month Unlimited-Mileage Warranty
Nationwide Recovery
Free Engine Matching by Registration
M256 Specialists

Your Mercedes CLS 320 Engine

Vehicle
Mercedes CLS 320
Model
CLS
Variant
CLS 320
Fuel
Petrol or Diesel
Engine
M112, M272, OM642
Capacity
3.0L–3.5L
Generation
C219 (2004–2010) · C218 (2010–2018)
Rebuild From
£2,800
Not sure which engine you have?
The CLS 320 uses the M256 3.0-litre inline-six mild-hybrid engine — enter your registration below and we'll confirm your exact spec before you get a quote.
DVLA & VIN verified
100% secure & private
No obligation quote
Mercedes CLS 320Engine Rebuild Price
Starting From £2,800

Engine Code
OM642Rebuild From
£2,800

Generation
C218 (2010–2018)

Engine Code
M112Rebuild From
£3,200

Generation
C219 (2004–2010)

Engine Code
M272Rebuild From
£3,200

Generation
C219 (2004–2010) · C218 (2010–2018)
Exact price depends on condition and parts required — submit your reg for a fixed-price quote.
Mercedes CLS 320 Oil Leaks & Coolant System Wear (M256 I6)
The M256 is a sophisticated 3.0-litre inline-six with an integrated starter-generator and electric auxiliary compressor — a more modern and efficient design than the older M276 V6. We replace timing chains, bearings, water pump and gaskets as standard on every M256 rebuild.
Because the CLS 320 uses a completely different engine family from the V8 M178 fitted to the CLS 63 and GT 63 S, parts and rebuild specifications don't cross over between them.
Source: Established M256 specialist pattern — timing chain, bearing and gasket wear across integrated-starter-generator inline-six units.

Mercedes CLS 320ENGINE OPTIONS
Every CLS 320 is different. That's why we offer the right solution for your engine, your car and your budget.
REBUILDING YOUR CLS 320 ENGINE
We rebuild the engine your CLS 320 already has instead of selling you a used engine of unknown history — strip it down, pressure-test it, and replace every worn or damaged component (timing chains, bearings, water pump, gaskets) with updated OEM parts. Near-new performance with a 12-month unlimited-mileage warranty.
From £3,200RECONDITIONED CLS 320 ENGINES
A full strip-down, inspection and replacement of worn parts rather than a straight swap. If that's what you're after, our rebuild service is exactly that.
Learn moreREFURBISHED CLS 320 ENGINES
Restoring your existing engine to full working condition rather than replacing it outright. Our rebuild service covers this.
Learn moreREMANUFACTURED CLS 320 ENGINES
Built to original specification with updated components. That's consistent with what our rebuild service delivers on the M256.
Learn moreREPLACEMENT CLS 320 ENGINES
If your existing engine is beyond economical repair, we offer complete engine replacement and fitting – sourced and fitted by our team, with the same 12-month warranty.
Learn moreUSED CLS 320 ENGINES
Matched low-mileage used engines for when time is critical. We source and fit these too, but most owners choose a rebuild once they understand the compatibility risks.
Learn moreNOT SURE WHICH OPTION IS RIGHT FOR YOU?
Enter your registration below and we'll confirm your M256 and talk you through the best solution for your CLS 320, honestly.
Ask About Your OptionsOUR WORKSHOP
01RECOVERY COLLECTION
02M256 ENGINE STRIPPED FOR REBUILD INSPECTION
03VALVE COVERS & COOLANT COMPONENT WORK
04TECHNICIANS AT WORK
05ENGINE TESTING (RIG)
06COMPLETED & READY FOR REFIT
Real photos from our workshop — not stock imagery. This is what a genuine Mercedes CLS 320 rebuild looks like.
Mercedes CLS 320 ENGINE REBUILD PROCESS
WHAT MERCEDES CLS 320 OWNERS SAY
WE COVER YOUREXACT VEHICLE
Enter your registration below and we'll confirm your CLS 320 has the M256, along with an exact rebuild price.
WHY MERCEDES CLS 320 OWNERS CHOOSE US
Engine matched using VIN or registration number — confirms M112, M272 or OM642 before you're quoted
Genuine specialist workshop — not a broker
Specialist technicians with 10-15 years of experience
We don't swap your engine for an unknown used unit
Nationwide recovery, workshop rebuild
12 month unlimited-mileage warranty
All engine ancillaries serviced as part of the rebuild
Trade & public enquiries welcome
Dedicated advisor from quote to fit
OUR MOST RECENTMERCEDES RECOVERIES & REBUILDS
Real vehicles brought into our workshop. Open bonnets, stripped blocks, and cars ready for collection — this is what genuine engine work looks like.

Mercedes CLS 320
RECOVERY

Mercedes CLS 63
DIAGNOSTICS

Mercedes CLS
STRIPPED ENGINE

Mercedes CLS S
TIMING CHAIN REPLACEMENT

Mercedes CLS 320
IN FOR REBUILD

Mercedes CLS C
REBUILD IN PROGRESS
HOW IT WORKS
SEND YOURREGISTRATION
RECEIVE YOURFIXED-PRICE QUOTE
WE RECOVERYOUR CAR
REBUILD &REFIT
Most CLS models are recovered within a few hours of booking. Most rebuilds are completed within 3-5 working days.
Workshop slots fill up fast — book your recovery today.

LOOKING FOR A USED ORREPLACEMENT ENGINEINSTEAD?
We supply low-mileage, VIN-matched used units too, and offer full replacement and fitting. However, most CLS 320 owners choose a rebuild once they realise it removes compatibility risk and works out more cost-effective over the life of the car.
Enter your reg below — we'll show you every option, honestly.
ABOUT THE MERCEDES CLS 320 ENGINE

The CLS 320 was part of the original CLS range from 2004, spanning two generations: the C219 (2004–2010) and the C218 (2010–2018). The first-generation C219 used a choice of V6 engines — the M112 or M272 petrol units, or the OM642 diesel in some markets (though diesel variants were more commonly badged as CLS 350d from the C218 onward). From the C218 generation, the CLS 320 petrol continued with the M272, while diesel versions used the OM642. The CLS was discontinued entirely after the C257 in 2023 — no successor exists, but we continue to rebuild and replace engines for every one still on the road.
We continue to rebuild and replace M256 engines for every CLS 320 on the road.
MERCEDES CLS 320 ENGINE CODES
A 3.0-litre or 3.5-litre V6 petrol engine fitted to the earliest C219-generation CLS 320 from 2004 to 2006. No specific known issue has been independently confirmed for this engine in this application. We replace timing chains, bearings and gaskets as standard on every M112 rebuild.
Check Your M112 CLS 320A 3.0-litre or 3.5-litre V6 petrol engine fitted to the CLS 320 from approximately 2006 onwards, across both C219 and C218 generations. No specific known issue has been independently confirmed for this engine in this application. We replace timing chains, bearings and gaskets as standard on every M272 rebuild.
Check Your M272 CLS 320A 3.0-litre V6 diesel engine, badged as the CLS 350d from the C218 generation onward. This engine is known for swirl flap and injector wear — see the callout above. We replace swirl flaps, injector seals and the timing chain as standard on every OM642 rebuild.
Check Your OM642 CLS 320MERCEDES CLS 320 ENGINE COMPATIBILITY

Because the CLS 320 spans multiple engine codes across two generations, fitting the wrong replacement — or assuming an M272 part will work on an M112 or OM642 car — risks a compatibility problem that's expensive to unpick. Before we quote or supply anything, we confirm:
Your exact engine code (M256) via registration or VIN
Your generation (R190)
Drivetrain and ancillary specification
Any electronics or ECU considerations specific to your exact build
This is why we always start with your registration rather than a generic CLS quote — it protects you from paying for parts that don't fit your actual car.
MERCEDES CLS 320 APPLICATIONS BY GENERATION
MERCEDES CLS 320 ENGINES BY YEAR
From the R190's launch in 2023, the CLS 320 has used the M256 3.0-litre inline-six mild hybrid throughout. If you're unsure of your exact spec, we'll confirm it before you book.
The M256 has been fitted to every CLS 320 since launch — if your registration year isn't listed above, get in touch and we'll confirm availability directly against your reg.
WE COVER EVERY MERCEDES CLS 320 MODEL YEAR:
Mercedes CLS 320
2004 Engine Rebuild
Mercedes CLS 320
2005 Engine Rebuild
Mercedes CLS 320
2006 Engine Rebuild
Mercedes CLS 320
2007 Engine Rebuild
Mercedes CLS 320
2008 Engine Rebuild
Mercedes CLS 320
2009 Engine Rebuild
Mercedes CLS 320
2010 Engine Rebuild
Mercedes CLS 320
2011 Engine Rebuild
Mercedes CLS 320
2012 Engine Rebuild
Mercedes CLS 320
2013 Engine Rebuild
Mercedes CLS 320
2014 Engine Rebuild
Mercedes CLS 320
2015 Engine Rebuild
Mercedes CLS 320
2016 Engine Rebuild
Mercedes CLS 320
2017 Engine Rebuild
Mercedes CLS 320
2018 Engine Rebuild
If your registration year isn't listed above, get in touch — we'll confirm availability directly against your reg.
MERCEDES CLS 320 ENGINE COSTS
A Mercedes CLS 320 engine rebuild starts from
£2,800
A full replacement engine and fitting service is also available. Exact pricing depends on the condition of your existing engine and the parts required — submit your registration for a fixed-price quote within 30 minutes.

12 MONTH
UNLIMITED-MILEAGE
WARRANTY
MERCEDES CLS 320 ENGINE SIZES
• Mercedes CLS 320 3.0 Litre Engine (M256, I6)
MERCEDES CLS 320 FUEL TYPES
• Mercedes CLS 320 Petrol Mild Hybrid Engine Rebuilds
RELATED MERCEDES CLS VARIANTS
Most Mercedes CLS engine rebuilds are completed within 3-5 working days.
Nationwide recovery and collection available for all CLS models.









