Mercedes Benz SLC 43 AMG Engine ReplacementCompare Prices & Get Quotes
Get quotes today from trusted UK Mercedes Benz SLC 43 AMG engine specialists. Compare prices on reconditioned, rebuilt and used engines for the hand-built 3.0-litre V6 biturbo - supply & fit available nationwide.
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12-Month Warranty
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From £5,500 to £9,600
Used from £2,500 · Reconditioned from £5,500 · Common codes: M276.823
From £2,500
Tested, bare/short engine
From £5,500
Rod bearings addressed, tested
From quote
Upgraded bearings, full teardown, revised valvetrain
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3 Simple Steps3 Simple Stepsto Finding the Best Mercedes Benz SLC 43 AMG Replacement Engineto Finding the Best Mercedes Benz SLC 43 AMG Replacement Engine
Most replacements completed within 3-5 days.
Variant HistoryMercedes Benz SLC 43 AMG - Engine History & Specs at a Glance
The SLC 43 AMG launched in 2016 as the flagship performance variant of the R172 SLC range, replacing the V8-powered SLK 55 AMG with a downsized but potent 3.0-litre V6 biturbo. Powered by the M276.823 engine producing 367hp and 520Nm of torque, it delivered 0-100 km/h in 4.7 seconds - just one-tenth slower than its V8 predecessor while offering improved efficiency. Production continued until 2020 when the SLC was discontinued, making the SLC 43 AMG the final performance roadster from Mercedes in this lineage.
Variant HistoryMercedes Benz SLC 43 AMG - Engine History & Specs at a Glance
The SLC 43 AMG launched in 2016 as the flagship performance variant of the R172 SLC range, replacing the V8-powered SLK 55 AMG with a downsized but potent 3.0-litre V6 biturbo. Powered by the M276.823 engine producing 367hp and 520Nm of torque, it delivered 0-100 km/h in 4.7 seconds - just one-tenth slower than its V8 predecessor while offering improved efficiency. Production continued until 2020 when the SLC was discontinued, making the SLC 43 AMG the final performance roadster from Mercedes in this lineage.
Mercedes Benz SLC 43 AMG
Fuel TypePetrol (twin-turbo V6 with direct injection)
Engine Size3.0L (2,996cc)Displacement2,996 ccEngine History Timeline
M276.823 3.0L V6 biturbo, 367hp @ 5,500-6,000rpm, 520Nm @ 2,000-4,200rpm (SLC 43 AMG, R172 launch)
M276.823 3.0L V6 biturbo, 390hp (SLC 43 AMG power upgrade)
2020 - Both power outputs paired with 9G-TRONIC sports transmission
End of SLC production; R172 platform retired
Key Specs Snapshot
Fuel TypePetrol (twin-turbo V6 with direct injection)Engine Size3.0L (2,996cc)Displacement2,996 cc
Power Output Range367-390hp across the variant's historyYears Produced2016-2020Every engine fitted to the Mercedes Benz SLC 43 AMG is covered below, with UK rebuilt pricing and known failure points - from M276 timing chain tensioner wear and carbon buildup to turbocharger and PCV system issues.
Mercedes Benz SLC 43 AMG Engine Codes - Specifications & Replacement CostMercedes Benz SLC 43 AMG Engine Codes - Specifications & Replacement Cost
3.0L V6 Biturbo (2016-2020)
Power Output367 hp (270 kW) @ 5,500-6,000 rpm (2016-2018); 390 hp (2018-2020)Torque520 Nm @ 2,000-4,200 rpmYears Fitted2016-2020Displacement2,996 ccCylindersV6, 24-valve, twin-turbocharged with direct injectionEngine CodeM 276.823
Compatible Trim Levels
- SLC 43 AMG
- SLC 43 AMG 4MATIC (R172)
Find your exact engine code, specs and UK replacement cost guide.
Used
Tested, ready-to-fit engine
£2,500-£4,000
Reconditioned
Addressed known issues, tested
£5,500-£7,500
Rebuilt
Full teardown, upgraded internals
£6,500-£9,600
Common Failure
Timing chain tensioner wear - the M276 engine can suffer from secondary chain tensioner issues, resulting in a rattling noise on cold starts. The hydraulic tensioners are a known weak point, with a simple hard rubber bearing that can leak oil pressure. Carbon buildup on intake valves is common on direct injection engines, causing rough idle and reduced performance. Turbocharger issues, PCV system failures, and oil cooler leaks have also been reported. Typical failure mileage: 50,000-90,000 miles.
The SLC 43 AMG's M276 V6 biturbo is a hand-built AMG performance engine - powerful, responsive and the heart of Mercedes' compact roadster flagship. However, like any high-performance engine, it has well-documented weaknesses that can lead to significant repair costs. Timing chain tensioner wear, carbon buildup on intake valves, turbocharger issues, and PCV system failures are the most common problems driving replacement enquiries. Every rebuilt engine supplied through EnginesMarket includes upgraded components addressing these original failure points, plus a minimum 12-month unlimited-mileage warranty.
The SLC 43 AMG's Most Critical Weakness
Affected Vehicles
Mercedes SLC 43 AMG (M276.823, 2016-2020)
Typical Failure Mileage
50,000-90,000 miles
Root Cause
The M276 engine suffers from secondary chain tensioner issues, resulting in a rattling noise on cold starts. The hydraulic tensioners are extra-weak, made with a simple hard rubber bearing that can leak oil pressure. A failing timing chain tensioner typically produces a rattling or knocking sound from the front of the engine, especially when the engine is cold or during hard acceleration. If ignored, the timing chain can stretch, leading to poor timing performance and misfires.
Why It Happens
The M276 engine suffers from secondary chain tensioner issues, resulting in a rattling noise on cold starts. The hydraulic tensioners are extra-weak, made with a simple hard rubber bearing that can leak oil pressure. A failing timing chain tensioner typically produces a rattling or knocking sound from the front of the engine, especially when the engine is cold or during hard acceleration. If ignored, the timing chain can stretch, leading to poor timing performance and misfires.
Dealer (parts + labour)
£300-£500
Specialist (parts + labour)
£200-£350
What it involves
Timing chain inspection, camshaft correlation check, diagnostic scan
Suitability
First step - confirms whether tensioner or chain is the issue
1 - 2 daysDealer (parts + labour)
£1,800-£2,800
Specialist (parts + labour)
£1,200-£1,800
What it involves
Replace secondary chain tensioners, install check valves per MB TSB
Suitability
Effective if caught early before chain stretch occurs
1 - 2 daysDealer (parts + labour)
£3,500-£5,500
Specialist (parts + labour)
£2,400-£3,600
What it involves
Replace timing chains, guides, tensioners, camshaft sprockets
Suitability
If rattle has persisted and chain stretch is confirmed
1 - 2 daysDealer (parts + labour)
£8,000-£12,000
Specialist (parts + labour)
£6,500-£9,600
What it involves
Complete engine swap with upgraded timing components, 12-month warranty
Suitability
If timing failure has caused valve damage
1 - 2 daysAll prices are indicative UK market ranges based on current UK specialist supplier data.| Repair Tier | Dealer (Parts + Labour) | Specialist (Parts + Labour) | What It Involves | Suitability | Estimated Time |
|---|---|---|---|---|---|
 Diagnostics - Timing chain inspection Minor | £300-£500 | £200-£350 | Timing chain inspection, camshaft correlation check, diagnostic scan | First step - confirms whether tensioner or chain is the issue | 1 - 2 days |
 Intermediate - Tensioner & check valve replacement Best Value | £1,800-£2,800 | £1,200-£1,800 | Replace secondary chain tensioners, install check valves per MB TSB | Effective if caught early before chain stretch occurs | 1 - 2 days |
Major - Full timing chain kit Best Value | £3,500-£5,500 | £2,400-£3,600 | Replace timing chains, guides, tensioners, camshaft sprockets | If rattle has persisted and chain stretch is confirmed | 1 - 2 days |
Full Replacement - Rebuilt M276 engine Best Value | £8,000-£12,000 | £6,500-£9,600 | Complete engine swap with upgraded timing components, 12-month warranty | If timing failure has caused valve damage | 1 - 2 days |
Vehicle Value Check
Vehicle Value Check
A typical 2016-2020 SLC 43 AMG is worth approximately £18,000-£35,000 depending on mileage and condition. These premium AMG roadsters retain strong values for well-maintained examples, making engine replacement a justifiable investment.
Our Recommendation
Our Recommendation
If your SLC 43 AMG exhibits a rattling noise on cold start, act immediately. The M276's secondary chain tensioners are a known critical weakness. Specialist timing chain tensioner replacement at £1,200-£1,800 is significantly cheaper than dealer rates. If the chain has jumped timing, a full rebuilt M276 engine with upgraded timing components is the only safe option. The M276 is a better engine than the M272, but you will have to replace timing chain components by no later than 250k miles on it.
Don't Let Timing Chain Wear, Carbon Buildup, or Turbo Issues Write Off Your Mercedes SLC 43 AMG
Whether you're facing M276 timing chain tensioner wear on your SLC 43 AMG, carbon buildup on intake valves, or turbocharger issues, EnginesMarket makes it simple to compare quotes from trusted UK Mercedes AMG specialists. Every rebuilt engine in our network carries upgraded components addressing the original design weakness - reinforced timing chain tensioners, clean intake valves, and fresh turbo components - plus a minimum 12-month unlimited mileage warranty with nationwide delivery and supply & fit options. Don't pay main dealer premiums. Compare prices from independent AMG specialists who know this hand-built V6 biturbo engine inside out.
Compare rebuilt M276 Mercedes SLC 43 AMG engine prices
12-Month Minimum
UK Specialists Vetted
Best Price GuidanceImportant Information
Important Information
"All prices are indicative UK market ranges based on historical quote data and repair requests from our network of engine specialists. Dealer pricing is estimated based on published main dealer labour rates and genuine OEM parts pricing. Specialist pricing reflects actual quote data from EnginesMarket's UK network. Actual costs vary depending on damage severity, vehicle condition, variant, and workshop location within the UK. Use our free comparison tool to get tailored quotes for your specific Mercedes SLC 43 AMG. Every engine supplied through EnginesMarket carries a minimum 12-month unlimited mileage warranty - always confirm exact terms with your chosen supplier."
Mercedes Benz SLC 43 AMG Engine ReplacementFrequently Asked Questions
Question 1How much does a Mercedes SLC 43 AMG engine replacement cost in the UK-
Short summary: A rebuilt M276 engine for the SLC 43 AMG costs £6,500-£9,600 supply-only. Fitting adds £1,200-£2,000 depending on complexity - AMG V6 biturbo work requires specialist knowledge.
- SLC 43 AMG (M276.823): rebuilt unit £6,500-£9,600; used engine from £2,500
- M276 timing chain tensioner replacement: £1,200-£1,800 at specialist
- M276 walnut blasting (carbon cleaning): £400-£700 at specialist
Question 2What are the signs of timing chain tensioner failure on a Mercedes SLC 43 AMG-
Short summary: A rattling or knocking noise on cold start lasting a few seconds is the classic warning sign on the M276 engine. The hydraulic secondary chain tensioners are a known weak point on the M276. If ignored, it can lead to chain stretch, poor timing performance, misfires and catastrophic engine failure.
- Rattling or knocking noise on cold start - earliest warning
- Poor timing performance and misfires
- Check engine light with timing correlation codes
- If caught early, tensioner replacement costs £1,200-£1,800 at specialist
Question 3What causes carbon buildup on a Mercedes SLC 43 AMG-
Short summary: Carbon buildup on intake valves is a known issue on direct injection engines like the M276. Because fuel is injected directly into the combustion chamber, intake valves are not washed by fuel, allowing carbon deposits to accumulate over time.
- Rough idle and reduced performance
- Poor fuel economy
- Regular intake valve cleaning (walnut blasting) is recommended
- If caught early, cleaning costs £400-£700 at specialist
Question 4Is the Mercedes SLC 43 AMG engine (M276) reliable-
Short summary: The M276 is a hand-built AMG performance engine - powerful and refined, but it has known weaknesses. Timing chain tensioner wear, carbon buildup, turbocharger issues, and PCV system failures are the most common problems. Generally a durable, refined engine - 200,000+ km examples are common - but has well-documented weak points. With these addressed and regular maintenance, the engine is capable of 150,000+ miles.
- M276 is fundamentally strong with proper maintenance
- Timing chain tensioner wear is the most critical issue - early intervention is key
- Carbon buildup is a maintenance item on direct injection engines
- Regular oil changes with Mercedes-spec oil are essential
Question 5How long do Mercedes SLC 43 AMG engines last-
Short summary: Properly maintained M276 engines routinely reach 150,000-200,000 miles before major work. Timing chain issues typically appear between 50,000-90,000 miles.
- M276 (SLC 43 AMG): 150,000-200,000 miles with regular servicing
- Timing chain tensioner inspection recommended from 50,000 miles
- Carbon cleaning recommended from 40,000-60,000 miles
- Service interval is 10,000 miles or 12 months - use Mercedes-spec MB 229.5 oil
Question 6Is it worth replacing the engine in my Mercedes SLC 43 AMG-
Short summary: Yes, if the SLC is otherwise in good condition with no rust or major transmission faults. A rebuilt M276 costs £6,500-£9,600 - far less than replacing a £18,000-£35,000 vehicle. SLC 43 AMG values remain strong for well-maintained examples, making engine replacement a worthwhile investment.
- SLC 43 AMG values: £18,000-£35,000 depending on condition and mileage
- Rebuilt engine with upgraded components fixes original weak points
- Supply & fit typically £7,700-£11,600 depending on engine code
- New engine includes 12-month unlimited mileage warranty
Why Choose UsCompare Mercedes SLC 43 AMGEngine PricesToday
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supply & fit available for M276
Comparing quotes for your Mercedes SLC 43 AMG is completely free, with no obligation and no pressure. Enter your registration above to get tailored quotes from UK Mercedes AMG specialists who understand the M276 V6 biturbo engine inside out. Whether you need a used engine, a reconditioned unit, or a full rebuilt engine with upgraded timing chain tensioners, clean intake valves, and fresh turbo components, we'll connect you with the right specialist for your exact SLC - with a minimum 12-month warranty on every engine supplied.
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