Mercedes SL400Engine Rebuild— From £3,200
Specialist Mercedes SL400 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 SL400 Engine
Vehicle
Mercedes SL400
Model
SL
Variant
SL400
Fuel
Petrol Twin-Turbo
Engine
M276
Capacity
3.0L V6
Generation
R231 (2012–2021)
Rebuild From
£3,200
Not sure which engine you have?
The SL400 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 SL400Engine Rebuild Price
Starting From £3,200
Engine Code
M276Rebuild From
£3,200
Generation
R231 (2012–2021)
Exact price depends on condition and parts required — submit your reg for a fixed-price quote.
Mercedes SL400 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 SL400 uses a completely different engine family from the V8 M178 fitted to the SL 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 SL400ENGINE OPTIONS
Every SL400 is different. That's why we offer the right solution for your engine, your car and your budget.
REBUILDING YOUR SL400 ENGINE
We rebuild the engine your SL400 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 SL400 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 SL400 ENGINES
Restoring your existing engine to full working condition rather than replacing it outright. Our rebuild service covers this.
Learn moreREMANUFACTURED SL400 ENGINES
Built to original specification with updated components. That's consistent with what our rebuild service delivers on the M256.
Learn moreREPLACEMENT SL400 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 SL400 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 SL400, 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 SL400 rebuild looks like.
Mercedes SL400 ENGINE REBUILD PROCESS
WHAT MERCEDES SL400 OWNERS SAY
WE COVER YOUREXACT VEHICLE
Enter your registration below and we'll confirm your SL400 has the M256, along with an exact rebuild price.
WHY MERCEDES SL400 OWNERS CHOOSE US
Engine matched using VIN or registration number
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 SL400
RECOVERY
Mercedes SL 63
DIAGNOSTICS
Mercedes SL
STRIPPED ENGINE
Mercedes SL S
TIMING CHAIN REPLACEMENT
Mercedes SL400
IN FOR REBUILD
Mercedes SL C
REBUILD IN PROGRESS
HOW IT WORKS
SEND YOURREGISTRATION
RECEIVE YOURFIXED-PRICE QUOTE
WE RECOVERYOUR CAR
REBUILD &REFIT
Most SL 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 SL400 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 SL400 ENGINE
The SL400 was introduced with the R231 generation in 2012, replacing the SL350 as the V6 entry point to the SL range. It uses the M276 — a 3.0-litre twin-turbo V6 that represented a significant step forward from Mercedes' earlier naturally aspirated V6 engines. The R231 SL400 continued through to 2021, when the SL moved to an AMG-only lineup with the R232 generation. The SL400 is no longer in production, 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 SL400 on the road.
MERCEDES SL400 ENGINE CODES
M256 (R190, 2023–present)
A 3.0-litre inline-six petrol mild-hybrid engine fitted to the SL400 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 SL400MERCEDES SL400 ENGINE COMPATIBILITY
The SL400 uses a single engine code — the M276 — across its entire R231 production run. This makes compatibility simpler than on models that span multiple engine families. However, the M276 went through several revisions during its production life, and the exact specification can vary by model year. 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 SL quote — it protects you from paying for parts that don't fit your actual car.
MERCEDES SL400 APPLICATIONS BY GENERATION
Generation
Chassis
Years
Engine Code
Fuel
MERCEDES SL400 ENGINES BY YEAR
From the R190's launch in 2023, the SL400 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 SL400 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 SL400 MODEL YEAR:
Mercedes SL400
2012 Engine Rebuild
Mercedes SL400
2013 Engine Rebuild
Mercedes SL400
2014 Engine Rebuild
Mercedes SL400
2015 Engine Rebuild
Mercedes SL400
2016 Engine Rebuild
Mercedes SL400
2017 Engine Rebuild
Mercedes SL400
2018 Engine Rebuild
Mercedes SL400
2019 Engine Rebuild
Mercedes SL400
2020 Engine Rebuild
Mercedes SL400
2021 Engine Rebuild
If your registration year isn't listed above, get in touch — we'll confirm availability directly against your reg.
MERCEDES SL400 ENGINE COSTS
A Mercedes SL400 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 SL400 ENGINE SIZES
• Mercedes SL400 3.0 Litre Engine (M256, I6)
MERCEDES SL400 FUEL TYPES
• Mercedes SL400 Petrol Mild Hybrid Engine Rebuilds
RELATED MERCEDES SL VARIANTS
Most Mercedes SL engine rebuilds are completed within 3-5 working days.
Nationwide recovery and collection available for all SL models.