Mercedes S450Engine Rebuild— From £3,200
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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 S450 Engine
Vehicle
Mercedes S450
Model
S-Class
Variant
S450
Fuel
Petrol
Engine
M256
Capacity
3.0L I6
Generation
W222 (2017–2020) · W223 (2020–present)
Rebuild From
£3,200
Not sure which engine you have?
The S450 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 S450Engine Rebuild Price
Starting From £3,200
Engine Code
M256Rebuild From
£3,200
Generation
R190 (2023–present)
Exact price depends on condition and parts required — submit your reg for a fixed-price quote.
Mercedes S450 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 S450 uses a completely different engine family from the V8 M178 fitted to the S-Class 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 S450ENGINE OPTIONS
Every S450 is different. That's why we offer the right solution for your engine, your car and your budget.
REBUILDING YOUR S450 ENGINE
We rebuild the engine your S450 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 S450 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 S450 ENGINES
Restoring your existing engine to full working condition rather than replacing it outright. Our rebuild service covers this.
Learn moreREMANUFACTURED S450 ENGINES
Built to original specification with updated components. That's consistent with what our rebuild service delivers on the M256.
Learn moreREPLACEMENT S450 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 S450 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 S450, honestly.
Ask About Your Options
OUR 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 S450 rebuild looks like.
Mercedes S450 ENGINE REBUILD PROCESS
WHAT MERCEDES S450 OWNERS SAY
WE COVER YOUREXACT VEHICLE
Enter your registration below and we'll confirm your S450 has the M256, along with an exact rebuild price.
WHY MERCEDES S450 OWNERS CHOOSE US
Engine matched using VIN or registration number — confirms your exact S450 spec 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 *No widely-reported engine issue for this variant — we still recommend a full inspection before any long journey.*
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 S450
RECOVERY
Mercedes S-Class 63
DIAGNOSTICS
Mercedes S-Class
STRIPPED ENGINE
Mercedes S-Class S
TIMING CHAIN REPLACEMENT
Mercedes S450
IN FOR REBUILD
Mercedes S-Class C
REBUILD IN PROGRESS
HOW IT WORKS
SEND YOURREGISTRATION
RECEIVE YOURFIXED-PRICE QUOTE
WE RECOVERYOUR CAR
REBUILD &REFIT
Most S-Class 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 S450 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 S450 ENGINE
The S450 was introduced to the S-Class range in 2017 with the W222 generation, using the then-new M256 3.0-litre inline-six petrol engine. This engine marked a departure from the older M276 V6 that had been used in preceding S-Class variants. The M256 was the first application of a 48-volt mild-hybrid system on a series-production inline-six for Mercedes-Benz, and it remains in production with the current W223 generation S450, where it continues to serve as the entry-level petrol option. Knowing that your S450 uses the M256 regardless of generation helps confirm the correct components and rebuild approach from the outset.
We continue to rebuild and replace M256 engines for every S450 on the road.
MERCEDES S450 ENGINE CODES
M256 (R190, 2023–present)
A 3.0-litre inline-six petrol mild-hybrid engine fitted to the S450 from 2023 to present. The M256 features an integrated starter-generator (ISG) and electric auxiliary compressor, making it 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.
Check Your M256 S450MERCEDES S450 ENGINE COMPATIBILITY
The S450 has used the M256 engine across both of its generations (W222 and W223). While the core engine block and architecture are shared, there are slight revisions between the earlier and later applications. 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 S-Class quote — it protects you from paying for parts that don't fit your actual car.
MERCEDES S450 ENGINES BY YEAR
From the R190's launch in 2023, the S450 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 S450 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 S450 MODEL YEAR:
Mercedes S450
2017 Engine Rebuild
Mercedes S450
2018 Engine Rebuild
Mercedes S450
2019 Engine Rebuild
Mercedes S450
2020 Engine Rebuild
Mercedes S450
2021 Engine Rebuild
Mercedes S450
2022 Engine Rebuild
Mercedes S450
2023 Engine Rebuild
Mercedes S450
2024 Engine Rebuild
Mercedes S450
2025 Engine Rebuild
Mercedes S450
2026 Engine Rebuild
If your registration year isn't listed above, get in touch — we'll confirm availability directly against your reg.
MERCEDES S450 ENGINE COSTS
A Mercedes S450 engine rebuild starts from
£3,200
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 S450 ENGINE SIZES
• Mercedes S450 3.0 Litre Engine (M256, I6)
MERCEDES S450 FUEL TYPES
• Mercedes S450 Petrol Mild Hybrid Engine Rebuilds
RELATED MERCEDES S-CLASS VARIANTS
Most Mercedes S-Class engine rebuilds are completed within 3-5 working days.
Nationwide recovery and collection available for all S-Class models.