Mercedes Benz SLK 250/350 Engine ReplacementCompare Prices & Get Quotes
Get quotes today from trusted UK Mercedes Benz SLK 250 and SLK 350 engine specialists. Compare prices on reconditioned, rebuilt and used engines for the 1.8-litre turbo four-cylinder and the 3.5-litre V6 - supply & fit available nationwide.
Supply & Fit Available
12-Month Warranty
Nationwide Delivery
100+ Suppliers
From £1,800 to £5,200
Used from £1,000 · Reconditioned from £1,800 · Common codes: M271.861, M272.963, M272.969, M276.956
From £1,000
Tested, bare/short engine
From £1,800
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 SLK 250/350 Replacement Engineto Finding the Best Mercedes Benz SLK 250/350 Replacement Engine
Most replacements completed within 3-5 days.
Variant HistoryMercedes Benz SLK 250/350 - Engine History & Specs at a Glance
The SLK 250 and SLK 350 have represented the core of the SLK range across the R171 and R172 generations. The SLK 250 launched in the R172 generation in 2011, powered by the M271 1.8-litre turbocharged four-cylinder producing 204hp - a direct-injection evolution of the earlier Kompressor engines. The SLK 350 has spanned both generations: the R171 SLK 350 (2004-2010) used the M272 3.5-litre naturally aspirated V6 producing 272hp, while the R172 SLK 350 (2011-2016) received the M276 3.5-litre V6 producing 306hp. These engines represent the heart of the SLK range, balancing performance with everyday usability.
Variant HistoryMercedes Benz SLK 250/350 - Engine History & Specs at a Glance
The SLK 250 and SLK 350 have represented the core of the SLK range across the R171 and R172 generations. The SLK 250 launched in the R172 generation in 2011, powered by the M271 1.8-litre turbocharged four-cylinder producing 204hp - a direct-injection evolution of the earlier Kompressor engines. The SLK 350 has spanned both generations: the R171 SLK 350 (2004-2010) used the M272 3.5-litre naturally aspirated V6 producing 272hp, while the R172 SLK 350 (2011-2016) received the M276 3.5-litre V6 producing 306hp. These engines represent the heart of the SLK range, balancing performance with everyday usability.
Mercedes Benz SLK 250/350
Fuel TypePetrol (M271: turbocharged four-cylinder; M272/M276: naturally aspirated V6)
Engine Size Range1.8L-3.5L (M271: 1,796cc; M272/M276: 3,498cc)
Power Output Range204-306hp across the variant's historyEngine History Timeline
M272.963 3.5L naturally aspirated V6, 272hp @ 6,000rpm (SLK 350, R171 launch)
M272.969 3.5L V6, 272hp (SLK 350 Sport, R171)
M271.861 1.8L turbocharged four-cylinder, 204hp @ 5,500rpm (SLK 250, R172 launch)
M276.956 3.5L naturally aspirated V6, 306hp @ 6,500rpm (SLK 350, R172 launch)
Key Specs Snapshot
Fuel TypePetrol (M271: turbocharged four-cylinder; M272/M276: naturally aspirated V6)Engine Size Range1.8L-3.5L (M271: 1,796cc; M272/M276: 3,498cc)Power Output Range204-306hp across the variant's historyYears Produced2004-2016Every engine fitted to the Mercedes Benz SLK 250 and 350 is covered below, with UK rebuilt pricing and known failure points - from M271 timing chain stretch to M272 balance shaft failure and M276 timing chain tensioner wear.
Mercedes Benz SLK 250/350 Engine Codes - Specifications & Replacement CostMercedes Benz SLK 250/350 Engine Codes - Specifications & Replacement Cost
1.8L Turbocharged Four-Cylinder (2011-2015)
Power Output204 hp (150 kW) @ 5,500 rpmTorque310 Nm @ 2,000-4,300 rpmYears Fitted2011-2015Displacement1,796 ccCylindersInline 4, DOHC, 16-valve, turbocharged with direct injectionEngine CodeM 271 E 18 DE LA / 271.861
Compatible Trim Levels
- SLK 250
- SLK 250 BlueEFFICIENCY (R172)
Find your exact engine code, specs and UK replacement cost guide.
Used
Tested, ready-to-fit engine
£1,000-£1,800
Reconditioned
Addressed known issues, tested
£1,800-£2,800
Rebuilt
Full teardown, upgraded internals
£2,200-£3,500
Common Failure
Timing chain stretch and guide wear - the M271 engine is notorious for timing chain elongation, often caused by a failing tensioner. The plastic timing chain guides can wear down, exacerbating the issue. Cold-start rattling is the classic warning sign. Camshaft adjuster sprocket wear and camshaft adjuster magnet failure are also common.
The SLK 250's M271 turbo four-cylinder and the SLK 350's M272/M276 V6s are among Mercedes' most popular engines, but each has well-documented weaknesses that can lead to significant repair costs. The M271 is notorious for timing chain stretch, while the M272 suffers from balance shaft gear failure, and the M276 can develop timing chain tensioner wear. Every rebuilt engine supplied through EnginesMarket includes upgraded components addressing these original failure points, plus a minimum 12-month unlimited-mileage warranty.
The SLK 250's Critical Weakness
Affected Vehicles
Mercedes SLK 250 (M271.861, 2011-2015)
Typical Failure Mileage
60,000-100,000 miles
Root Cause
The M271 engine is notorious for timing chain elongation, which is often caused by a failing tensioner. The plastic timing chain guides can also wear down, exacerbating the issue. Extended oil change intervals or low-quality oil are the main causes.
Why It Happens
The M271 engine is notorious for timing chain elongation, which is often caused by a failing tensioner. The plastic timing chain guides can also wear down, exacerbating the issue. Extended oil change intervals or low-quality oil are the main causes.
Dealer (parts + labour)
£200-£400
Specialist (parts + labour)
£150-£300
What it involves
Timing chain inspection, camshaft correlation check
Suitability
First step - confirms whether chain or tensioner is the issue
1 - 2 daysDealer (parts + labour)
£1,800-£2,800
Specialist (parts + labour)
£1,200-£1,800
What it involves
Replace timing chain, guides, tensioner, camshaft adjuster
Suitability
If caught before chain stretch is severe
1 - 2 daysDealer (parts + labour)
£4,500-£6,500
Specialist (parts + labour)
£2,200-£3,500
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 | £200-£400 | £150-£300 | Timing chain inspection, camshaft correlation check | First step - confirms whether chain or tensioner is the issue | 1 - 2 days |
 Intermediate - Timing chain & tensioner replacement Best Value | £1,800-£2,800 | £1,200-£1,800 | Replace timing chain, guides, tensioner, camshaft adjuster | If caught before chain stretch is severe | 1 - 2 days |
Full Replacement - Rebuilt M271 engine Best Value | £4,500-£6,500 | £2,200-£3,500 | 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 2011-2015 SLK 250 is worth approximately £6,000-£15,000 depending on condition and mileage. The R172 retains strong values for well-maintained examples, making engine replacement a justifiable investment.
Our Recommendation
Our Recommendation
If your SLK 250 exhibits a rattling noise on cold start, act immediately. The M271's timing chain is a known critical weakness. Specialist timing chain replacement at £1,200-£1,800 is significantly cheaper than dealer rates. If the chain has jumped timing, a full rebuilt M271 engine with upgraded timing components is the only safe option.
Don't Let Timing Chain Stretch, Balance Shaft Failure, or Oil Leaks Write Off Your Mercedes SLK 250 or 350
Whether you're facing M271 timing chain stretch on your SLK 250, M272 balance shaft failure on your R171 SLK 350, or M276 timing chain rattle on your R172 SLK 350, EnginesMarket makes it simple to compare quotes from trusted UK Mercedes petrol specialists. Every rebuilt engine in our network carries upgraded components addressing the original design weakness - reinforced timing chains, updated balance shaft gears, and fresh gaskets and seals - 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 Mercedes specialists who know these SLK engines inside out.
Compare rebuilt M271 Mercedes SLK 250 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 SLK 250 or 350. Every engine supplied through EnginesMarket carries a minimum 12-month unlimited mileage warranty - always confirm exact terms with your chosen supplier."
Mercedes Benz SLK 250/350 Engine ReplacementFrequently Asked Questions
Question 1How much does a Mercedes SLK 250 or 350 engine replacement cost in the UK-
Short summary: A rebuilt M271 engine for the SLK 250 costs £2,200-£3,500 supply-only; a rebuilt M272 engine for the R171 SLK 350 costs £2,800-£4,200; a rebuilt M276 engine for the R172 SLK 350 costs £3,200-£5,200. Fitting adds £800-£1,500 depending on complexity - V6 work requires specialist knowledge.
- SLK 250 (M271.861): rebuilt unit £2,200-£3,500; used engine from £1,000
- SLK 350 (M272.963/969): rebuilt unit £2,800-£4,200; used engine from £1,200
- SLK 350 (M276.956): rebuilt unit £3,200-£5,200; used engine from £1,500
- M271 timing chain replacement: £1,200-£1,800 at specialist
- M272 balance shaft replacement: £2,100-£2,900 at specialist
Question 2What are the signs of timing chain failure on a Mercedes SLK 250-
Short summary: A rattling noise on cold start is the classic warning sign on the M271 engine. The timing chain can stretch over time, especially on earlier models, and the plastic timing chain guides can wear down.
- Rattling noise on cold start lasting 1-3 seconds - earliest warning
- Engine misfires or rough idling
- Check engine light with timing correlation codes
- Poor fuel economy and loss of power
- If caught early, timing chain replacement costs £1,200-£1,800 at specialist
Question 3What are the signs of balance shaft failure on a Mercedes SLK 350-
Short summary: Check engine light, rough running, and valve train clatter are the classic warning signs on the M272 engine. The balance shaft gear failure is a known catastrophic issue on early M272 V6 engines.
- Check engine light with P1200/P1208 fault codes
- Valve train clatter or metallic noise
- Rough running or misfiring
- If caught early, balance shaft replacement costs £2,100-£2,900 at specialist
Question 4Is the Mercedes SLK 250 or 350 engine reliable-
Short summary: The M271 turbo four-cylinder is generally reliable but the timing chain is a known weakness. The M272 V6 is smooth and refined but early units suffer from balance shaft issues. The M276 V6 largely resolves the balance shaft problems of its predecessor but can develop timing chain tensioner wear.
- M271 timing chain stretch is the main concern - early intervention is key
- M272 balance shaft failure affects pre-2008 engines - check engine number
- M276 is more reliable than M272 but tensioner wear is possible
- Regular oil changes with MB 229.5 spec oil are essential for all engines
Question 5How long do Mercedes SLK 250 and 350 engines last-
Short summary: Properly maintained M271 engines routinely reach 150,000-200,000 miles before major work. The M272 can achieve similar mileage but may require balance shaft attention between 50,000-90,000 miles. The M276 is too new for definitive long-term data but is showing good durability.
- M271 (SLK 250): 150,000-200,000 miles with regular servicing
- M272 (SLK 350): 150,000-200,000 miles - balance shaft inspection from 50k miles
- M276 (SLK 350): too early for definitive data - tensioner issues from 60k 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 SLK 250 or 350-
Short summary: Yes, if the SLK is otherwise in good condition with no rust or major transmission faults. A rebuilt M271 costs £2,200-£3,500 - far less than replacing a £6,000-£18,000 vehicle. SLK values remain strong for well-maintained examples, making engine replacement a worthwhile investment.
- SLK 250 values: £6,000-£15,000 depending on condition and mileage
- SLK 350 values: £4,000-£18,000 depending on generation and condition
- Rebuilt engine with upgraded components fixes original weak points
- Supply & fit typically £3,000-£6,700 depending on engine code
- New engine includes 12-month unlimited mileage warranty
Why Choose UsCompare Mercedes SLK 250/350Engine PricesToday
500+ M271 and M272/M276 engines supplied through our network
12-Month Warranty on every rebuilt SLK 250 and 350 engine
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supply & fit available for M271, M272 and M276
Comparing quotes for your Mercedes SLK 250 or 350 is completely free, with no obligation and no pressure. Enter your registration above to get tailored quotes from UK Mercedes petrol specialists who understand the M271, M272 and M276 engines inside out. Whether you need a used engine, a reconditioned unit, or a full rebuilt engine with upgraded timing components, balance shaft gears, and seals, we'll connect you with the right specialist for your exact SLK - with a minimum 12-month warranty on every engine supplied.
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