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Mercedes-Benz · Luxury · 2005–2013 Custom Search

Mercedes-Benz S-Klasse W221

Weaknesses, engine ratings and buying advice

1.0 / 5.0 · Based on 8 engine variants · How we rate

The Mercedes S-Class W221 (2005–2013) is the W220's successor — more tech, better build, more reliable. But still: running an S-Class isn't running a Polo.

Engine choice: M272 (3.5 V6, 200 kW/272 PS) — sensible all-rounder. BUT: balance shaft gear made of plastic wears — classic M272 fault, cold start rattle ($1,650–3,300). OM642 (3.0 CDI V6, 173–195 kW) — best long-distance diesel. EGR issues on short trips. M156 (6.2 V8, 386 kW) in S63 AMG — high-rev NA, cam adjusters can rattle.

Airmatic: much better than W220 but still consumables from 120,000 km. Rust: much better protected than W220.

Test-drive checklist: M272/M273 cold start (balance shaft rattle?), Airmatic level, all comfort features, OM642 DPF status.

2026 market: 2009–2012 with 75,000 miles $13,200–24,200. S63 AMG $27,500–49,500. Insider pick: S350 CDI (OM642) with Airmatic and full service book.

Most Fun Engine

612 PS

S 65 AMG · Benzin

630 hp V12 in the S-Class — The Ultimate Silent Assault

Legendary!
Problem Engine

525–585 PS

5.5L V8 BiTurbo Benzin

11 weaknesses

Stay Away!

Generations


Engine Overview

The Mercedes-Benz S-Klasse W221 is available with 10 engine variants — from 120 to 630 hp. 1 variants had engine changes — the model year is crucial.

S 250 CDI · Diesel· 204 PS
2011 2013

Widely used Mercedes diesel with aluminium block and steel liner. High mileages possible but known for injector seal issues, timing chain stretch and EGR problems.

  • !! Chain Tensioner Seal Leaking — Recall

    Over 100,000 vehicles recalled: the chain tensioner seal leaks, allowing engine oil to drip onto the exhaust system and potentially ignite.

    Symptoms: Dropping oil level, oil smell from engine bay, oily deposits under the vehicle, possible oil fire
    0–300 $
  • !! Timing Chain Stretch (Simplex Chain) from 150,000 km

    The OM651 uses a simplex timing chain. With short-trip driving and overdue oil change intervals the chain stretches.

    Symptoms: Light rattling noise on cold start from the rear of the engine, no fault code stored
    1,200–3,000 $
  • !! Piezo Injector Faults from 80,000 km

    Same Delphi piezo injector problems as in the DE18: 220 CDI and 250 CDI variants affected. Mercedes replaced them with solenoid injectors as part of a service action.

    Symptoms: Vibrations and rough running especially under acceleration, elevated fuel consumption
    1,500–3,500 $

+ 3 more engine weaknesses + vehicle weaknesses

S 320 CDI · Diesel· 235 PS
2006 2013

V6 diesel with common rail and piezo injectors. Powerful and refined. Known for blocked oil coolers, swirl flap failure and EGR problems. High mileages possible with good maintenance.

  • !! Oil Cooler Gaskets Leaking — Oil and Coolant Loss from 120,000 km

    The best-known problem of the OM642: the oil cooler gaskets in the V-section of the engine fail. Oil leaks into the coolant or externally. Particularly prone on vehicles built up to 2009.

    Symptoms: Oil loss warning, oil spots under the left side of the vehicle, oil streaks visible on the belt tensioner
    800–2,500 $
  • !! Swirl Flap Linkage Breaks — Plastic Joint Fails from 100,000 km

    The plastic linkages of the swirl flaps in the OM642 intake manifold break. Aluminium repair kits are available and more durable. In the event of complete failure there is a risk of debris entering the engine.

    Symptoms: Engine warning light, fault codes for intake flap/swirl flap, power loss particularly at low rpm
    200–800 $
  • !! Injector Seal Leaking — Soot Deposits and Diesel in Oil from 120,000 km

    Piezo injectors seal poorly from heat, diesel enters the engine oil. Oil loses lubrication properties, tar-like residue around injectors is the typical telltale sign.

    Symptoms: Rough idle, increased fuel consumption, knocking noises, oil level rising due to diesel contamination, engine oil smells of diesel
    300–900 $

+ 4 more engine weaknesses + vehicle weaknesses

S 350 CDI · Diesel· 258 PS
2010 2013

V6 diesel with common rail and piezo injectors. Powerful and refined. Known for blocked oil coolers, swirl flap failure and EGR problems. High mileages possible with good maintenance.

  • !! Oil Cooler Gaskets Leaking — Oil and Coolant Loss from 120,000 km

    The best-known problem of the OM642: the oil cooler gaskets in the V-section of the engine fail. Oil leaks into the coolant or externally. Particularly prone on vehicles built up to 2009.

    Symptoms: Oil loss warning, oil spots under the left side of the vehicle, oil streaks visible on the belt tensioner
    800–2,500 $
  • !! Swirl Flap Linkage Breaks — Plastic Joint Fails from 100,000 km

    The plastic linkages of the swirl flaps in the OM642 intake manifold break. Aluminium repair kits are available and more durable. In the event of complete failure there is a risk of debris entering the engine.

    Symptoms: Engine warning light, fault codes for intake flap/swirl flap, power loss particularly at low rpm
    200–800 $
  • !! Injector Seal Leaking — Soot Deposits and Diesel in Oil from 120,000 km

    Piezo injectors seal poorly from heat, diesel enters the engine oil. Oil loses lubrication properties, tar-like residue around injectors is the typical telltale sign.

    Symptoms: Rough idle, increased fuel consumption, knocking noises, oil level rising due to diesel contamination, engine oil smells of diesel
    300–900 $

+ 4 more engine weaknesses + vehicle weaknesses

S 420 CDI · Diesel· 320 PS
2006 2009

Successor to the OM628, from 2005 with revised common rail injection at 1,600 bar and piezo injectors. Power output rose to up to 320 hp at 730 Nm — the gearbox hit its limits early, prompting Mercedes to recalibrate the NAG2 mapping during series production. Mechanically the OM629 shares most challenges with its predecessor but adds its own: the oil cooler in the V-area tends to leak at high mileages and additionally promotes EGR fouling of the intake tract. Cylinder heads come under extreme pressure during high-rpm full-load pulls — warped heads are not uncommon beyond 200,000 km. Piezo injectors demand clean fuel and short oil change intervals (10,000 km, 229.51 or 229.52). Anyone taking on this engine should budget for preventive oil cooler and seal replacement early on.

  • !! Cylinder head warped -- coolant loss from 250,000 km

    Warped cylinder heads allow combustion gases into the cooling system. Overpressure constantly pushes coolant out through the expansion tank. Engine runs at temperature, coolant level drops steadily -- replacement costs 5,000-16,000 EUR.

    Symptoms: Coolant warning light despite stable engine temperature, coolant overflow from expansion tank, no visible external leak.
    5,000–16,000 $
  • !! NAG2 transmission at torque limit from 120,000 km

    The NAG2 automatic transmission is rated for approximately 700 Nm; the OM629 delivers up to 730 Nm. Early build years without shift module adaptation showed driveshaft failures and gearbox problems. Later revised.

    Symptoms: Shift jerks, gearbox fault messages, missed shifts, vibration on pull-away.
    1,500–5,000 $
  • !! Oil Cooler Leak in V-Section from 180,000 km

    The oil cooler sits at the lowest point in the V-section of the engine and seals with rubber gaskets. At high mileages oil seeps out, pools in the V and drips down. Repair takes approximately 2 days.

    Symptoms: Oil spots under the vehicle, oil mist in the V-section of the engine bay, elevated oil consumption.
    800–2,000 $

+ 3 more engine weaknesses + vehicle weaknesses

AMG S 63 · Petrol· 525–544 PS Engine Change
2006 2010

6.2-litre naturally aspirated V8, hand-built in Affalterbach to the 'One Man, One Engine' principle. 457–525 hp without any forced induction, rev limit at 7,200 rpm. The sound defines an era: a deep, bass-heavy rumble at 3,000 rpm, a scream above 5,000 that recalls American V8 racing engines. Throttle response is immediate — no turbo lag, no hesitation, every throttle command is executed instantly. Critical issue number one: camshafts wear out through inadequate cold-start lubrication with the factory 0W-40 oil. Switch to Ravenol 5W-40 RCS, let the engine idle for 10 seconds after a cold start, stay below 3,000 rpm until fully warm. Head bolt corrosion on engine numbers below 060658 (up to approx. 2010) — check without fail. Star Technical Bulletin 05.20/20b documents the tappet problem officially. Parts availability is becoming increasingly difficult — hydraulic tappets A1560500225 sometimes not available for months. Maintain the M156 properly and you have one of the most emotional V8s of the last 30 years.

  • !! Head Bolt Corrosion — Coolant in Combustion Chamber from 50,000 km

    All M156 up to engine number 060658 affected: head bolts corrode through coolant contact at the bolt head, in worst case break off. Coolant enters the combustion chamber — engine damage. Mercedes fitted improved bolts from approx. 2010 (20x A1560160769 + 4x N000000005754, approx. 108 EUR net). Preventive replacement strongly recommended.

    Symptoms: Coolant loss without visible leak, white smoke from exhaust, oil-coolant mixture, check engine light, misfires on individual cylinders.
    1,500–8,000 $
  • !! Camshaft Wear — Cold-Start Lubrication Deficit from 60,000 km

    Main problem of the M156: the factory 0W-40 oil drains from the camshafts at standstill; at cold start the lobes run briefly dry. Wear deteriorates exponentially. Camshaft regrinding (TechnoCam and others) as a cheaper alternative to new parts — 50% saving. Always replace the 32 hydraulic tappets (INA A1560500225) at the same time.

    Symptoms: Metallic ticking on cold start that disappears after 30–60 seconds, rough idle, power loss in the upper rev range. Remove valve cover and check lobe tips for wear.
    2,000–6,000 $
  • !! Camshaft Adjuster — Locking Plate Wears Out from 70,000 km

    The fit of the locking plate in the camshaft adjuster widens over time — the adjuster slips, timing shifts. Clattering on cold start is the first symptom. Reinforced locking plates (300–1,000 EUR for 4 pieces) as a permanent solution. Bearing cap torque 10 Nm, adjuster 45 Nm + 90°.

    Symptoms: Rattling/clattering on cold start for 2–10 seconds, disappears after oil pressure build-up. With advanced wear: also audible when warm, rough idle, shifted timing, power loss.
    800–3,000 $

+ 7 more engine weaknesses + vehicle weaknesses

2010 2013

5.5-litre V8 BiTurbo — AMG's first forced-induction V8 and the successor to the naturally aspirated M156. 525–585 hp depending on model, up to 900 Nm in the S version. The character is fundamentally different from the M156: instead of a high-revving scream, a brutal torque wave from 1,750 rpm. The sound is deeper, more bass-heavy, with a characteristic turbo hiss on lift-off. Less emotional than the naturally aspirated engine, but in a different league on the motorway — above 200 km/h the M157 still accelerates like others do at 100. Timing chain is the known Achilles heel: chain tensioner failure at 80,000–120,000 km, Mercedes has improved the design (non-return valve in cylinder head oil gallery). Piezo injectors are sensitive to fuel quality, service life 100,000–150,000 km. Turbos last 200,000+ km with proper warm-up and cool-down — shut off immediately after a motorway run and they'll fail significantly earlier. Warm up the engine, allow cool-down after hard use, oil changes every 10,000 km with 0W-40 — then 300,000 km is realistic.

  • !! Timing Chain Stretch — M157 BiTurbo V8 from 100,000 km

    The timing chains on the M157 5.5L BiTurbo V8 stretch, especially on vehicles with frequent cold starts and short trips. Engine damage possible if chain jumps. Extensive repair on the V8.

    Symptoms: Metallic rattling on cold start, camshaft position fault codes, rough running, in extreme cases engine damage
    3,000–8,000 $
  • !! Oil Consumption from Piston Ring Wear from 120,000 km

    Under heavy use the piston rings on the M157 wear prematurely. Oil consumption above 1 L/1,000 km is possible. Engine overhaul required with advanced wear.

    Symptoms: Rising oil consumption, blue smoke on acceleration, oil mist from exhaust, oil level warnings
    4,000–10,000 $
  • !! High-Pressure Fuel Pump Fails — No Fuel Pressure from 100,000 km

    The high-pressure fuel pump on the M157 can wear internally at high mileage. Pressure drop in the rail causes difficult starting and power loss.

    Symptoms: Difficult starting, power loss under load, hesitation at high rpm, fuel pressure fault codes
    1,200–3,000 $

+ 8 more engine weaknesses + vehicle weaknesses

S 350 · Petrol· 272 PS
2005 2013

Four-valve V6 with variable valve timing. Smooth and powerful. Known for balance shaft wear (revision sprocket) on early build years. Balance shaft gear problem addressed by Mercedes with a recall.

  • !! Balance Shaft Sprocket Wears Prematurely from 140,000 km

    The plastic balance shaft sprocket on the M272 wears prematurely from the timing chain. The right cylinder bank goes out of timing. Affected up to end of October 2006.

    Symptoms: Fault codes P0016/P0017 (camshaft right bank), chain rattling, rough running at idle, in extreme cases engine damage
    2,500–5,500 $
  • !! Timing Chain Stretches and Damages Timing from 120,000 km

    Alongside the balance shaft issue the M272 shows premature timing chain stretch. Chain wear on softer sprockets leads to timing deviations.

    Symptoms: Chain noise especially on cold start, camshaft fault codes, rough running, engine irregularities
    2,000–4,000 $
  • !! Camshaft Adjuster Leaks — Wiring Harness Contaminated from 90,000 km

    Four camshaft adjuster solenoids (two per cylinder bank) develop leaks; oil creeps into the wiring harness as far as the ECU. Repair costs up to €1,700 documented.

    Symptoms: CEL, oil traces at camshaft connectors, lambda sensor failure due to oil contamination, non-specific faults that recur
    100–1,700 $

+ 3 more engine weaknesses + vehicle weaknesses

S 450 · Petrol· 340 PS
2006 2010

Large-displacement naturally aspirated V8, second generation with variable valve timing on all four camshafts. Technically related to the M272 V6 — shares its known balance shaft sprocket problem on build years before 2007 (engine number below 088611). From that number the sprocket was made of hardened steel. Check early engines for fault codes P0016/P0017 and cold-start chain noise. The 5.5-litre with 285 kW is the typical variant; the 5.0-litre with 225–250 kW is somewhat more forgiving in heavier vehicles. The M278 BiTurbo successor is more efficient and more powerful, but sounds considerably less characterful — the M273 is the last true naturally aspirated V8 from Stuttgart. Pre-purchase: always check for camshaft adjuster leaks (oil in wiring harness) and thermostat fault P0128. Oil changes every 10,000 km with MB 229.5.

  • !! Balance shaft sprocket — same weakness as M272 from 140,000 km

    The M273 V8 shares the balance shaft sprocket issue with the M272 V6. The soft composite material of the sprocket wears down, causing timing chain rattle.

    Symptoms: Fault codes P0016/P0017, chain rattling, rough idle, power loss
    2,500–5,500 $
  • !! Camshaft Adjuster Leaking — Oil in Wiring Harness from 110,000 km

    As with the similarly-designed M272, the solenoid valves leak. The V8 has 4 per bank — consequential costs are particularly high due to more solenoids. Oil migrates by capillary action all the way to the ECU.

    Symptoms: Check engine light with camshaft fault codes P0014/P0015/P0021/P0025, lambda sensor failures, in extreme cases ECU failure
    200–2,000 $
  • !! Valve cover gaskets leaking on both sides from 130,000 km

    Like the M113, the valve cover gaskets on the M273 V8 become porous over time. With a V8 having two cylinder heads, the workload doubles.

    Symptoms: Oil spots under the vehicle, oil smell after hard driving, oily engine bay
    400–1,000 $

+ 6 more engine weaknesses + vehicle weaknesses

S 500 · Petrol· 388 PS
2005 2013

Large-displacement naturally aspirated V8, second generation with variable valve timing on all four camshafts. Technically related to the M272 V6 — shares its known balance shaft sprocket problem on build years before 2007 (engine number below 088611). From that number the sprocket was made of hardened steel. Check early engines for fault codes P0016/P0017 and cold-start chain noise. The 5.5-litre with 285 kW is the typical variant; the 5.0-litre with 225–250 kW is somewhat more forgiving in heavier vehicles. The M278 BiTurbo successor is more efficient and more powerful, but sounds considerably less characterful — the M273 is the last true naturally aspirated V8 from Stuttgart. Pre-purchase: always check for camshaft adjuster leaks (oil in wiring harness) and thermostat fault P0128. Oil changes every 10,000 km with MB 229.5.

  • !! Balance shaft sprocket — same weakness as M272 from 140,000 km

    The M273 V8 shares the balance shaft sprocket issue with the M272 V6. The soft composite material of the sprocket wears down, causing timing chain rattle.

    Symptoms: Fault codes P0016/P0017, chain rattling, rough idle, power loss
    2,500–5,500 $
  • !! Camshaft Adjuster Leaking — Oil in Wiring Harness from 110,000 km

    As with the similarly-designed M272, the solenoid valves leak. The V8 has 4 per bank — consequential costs are particularly high due to more solenoids. Oil migrates by capillary action all the way to the ECU.

    Symptoms: Check engine light with camshaft fault codes P0014/P0015/P0021/P0025, lambda sensor failures, in extreme cases ECU failure
    200–2,000 $
  • !! Valve cover gaskets leaking on both sides from 130,000 km

    Like the M113, the valve cover gaskets on the M273 V8 become porous over time. With a V8 having two cylinder heads, the workload doubles.

    Symptoms: Oil spots under the vehicle, oil smell after hard driving, oily engine bay
    400–1,000 $

+ 6 more engine weaknesses + vehicle weaknesses

S 600 · Petrol· 517 PS
2005 2013

Twelve cylinders, two turbochargers, a V-valley layout — technically fascinating and maintenance-intensive in equal measure. The fully encapsulated ignition module system with two banks at 1,400 EUR each is the most well-known cost factor; failure of both banks usually follows in quick succession. The oil-water heat exchanger in the V-valley almost always leaks eventually — factor in engine removal for the repair. The four camshaft solenoids fail to seal reliably after 80,000–100,000 km; oil creeps into the wiring harness and corrodes control units. Both turbochargers sit deep under the engine bay — removal and installation costs more than the turbo itself. Runs without issue beyond 300,000 km with diligent maintenance; what kills it is deferred servicing. Purchase requirement: complete service history, documented wiring harness check, no ABC alarm backlog, fresh ignition modules.

  • !! Ignition module bank failure (two banks at ~€1,400 each) from 120,000 km

    Both ignition module banks are fully potted wear items with a typical service life of 10–15 years. Failures tend to follow each other quickly. OEM cost approximately €1,400 each.

    Symptoms: Jerking and power loss, rough running, misfire codes P0307–P0312, petrol smell from the exhaust
    1,400–3,500 $
  • !! Turbocharger wear and wastegate wear from 180,000 km

    The two turbochargers show bearing and wastegate wear at high mileage. Engine removal is required for replacement; repair costs €2,000–4,000 per turbo.

    Symptoms: Whistling or rattling turbo noises, power loss under hard acceleration, blue smoke from oil loss
    2,000–8,000 $
  • !! ABC hydraulic lines and engine mounts — double defect from 100,000 km

    The M275 V12 Biturbo in the S600/CL600 puts extreme stress on the engine mounts due to its weight (>300 kg engine). At the same time, the ABC hydraulic lines age and leak. Both issues frequently occur together.

    Symptoms: ABC suspension hydraulic oil loss, engine sitting lower, vibrations in the cabin, ABC warning message
    2,000–5,000 $

+ 6 more engine weaknesses + vehicle weaknesses

S 65 AMG · Petrol· 612 PS
2006 2013

Twelve cylinders, two turbochargers, a V-valley layout — technically fascinating and maintenance-intensive in equal measure. The fully encapsulated ignition module system with two banks at 1,400 EUR each is the most well-known cost factor; failure of both banks usually follows in quick succession. The oil-water heat exchanger in the V-valley almost always leaks eventually — factor in engine removal for the repair. The four camshaft solenoids fail to seal reliably after 80,000–100,000 km; oil creeps into the wiring harness and corrodes control units. Both turbochargers sit deep under the engine bay — removal and installation costs more than the turbo itself. Runs without issue beyond 300,000 km with diligent maintenance; what kills it is deferred servicing. Purchase requirement: complete service history, documented wiring harness check, no ABC alarm backlog, fresh ignition modules.

  • !! Ignition module bank failure (two banks at ~€1,400 each) from 120,000 km

    Both ignition module banks are fully potted wear items with a typical service life of 10–15 years. Failures tend to follow each other quickly. OEM cost approximately €1,400 each.

    Symptoms: Jerking and power loss, rough running, misfire codes P0307–P0312, petrol smell from the exhaust
    1,400–3,500 $
  • !! Turbocharger wear and wastegate wear from 180,000 km

    The two turbochargers show bearing and wastegate wear at high mileage. Engine removal is required for replacement; repair costs €2,000–4,000 per turbo.

    Symptoms: Whistling or rattling turbo noises, power loss under hard acceleration, blue smoke from oil loss
    2,000–8,000 $
  • !! ABC hydraulic lines and engine mounts — double defect from 100,000 km

    The M275 V12 Biturbo in the S600/CL600 puts extreme stress on the engine mounts due to its weight (>300 kg engine). At the same time, the ABC hydraulic lines age and leak. Both issues frequently occur together.

    Symptoms: ABC suspension hydraulic oil loss, engine sitting lower, vibrations in the cabin, ABC warning message
    2,000–5,000 $

+ 6 more engine weaknesses + vehicle weaknesses

Vehicle Weaknesses

WeaknessCost
Airmatic air struts leaking

The air struts of the W221 wear over time. Between 200,000 and 300,000 km, all four struts typically need replacement.

Symptoms: Vehicle drops or sits lopsided, Airmatic fault message, compressor runs continuously
from 220,000 km
High
Pressure reservoir tank corroded (rear axle)

The Airmatic pressure reservoir tanks at the rear axle can corrode. Removal requires disassembly of the rear axle.

Symptoms: Airmatic fault message, pressure loss in system, vehicle drops after standing
from 180,000 km
High
!Airmatic air spring bags leaking — vehicle sits lopsided

Air spring bags (usually rear) become leaky and lose pressure gradually. The vehicle then sits 3–4 cm lower on one side. Fault code 5285 (fill process too long) appears. Repair is only possible by replacement.

Symptoms: Vehicle sits lopsided, warning 'vehicle too low' in instrument cluster, compressor runs frequently, yellow warning light
from 120,000 km
High

Test Reports

tuev

TÜV Report 2024

Average

The range sits in the mid-field of the luxury segment at main inspection, with strengths in lighting.

2023-11
pannenstatistik

ADAC Breakdown Statistics 2023

Average

Breakdown frequency at the class average, but electrical faults occur regularly.

2023-04
NHTSA Owner Complaints
Below average
233 complaints · 2005–2013
  1. 01 Electrical
    63
  2. 02 Engine
    41
  3. 03 Powertrain
    35 ⚠ 2
  4. 04 Suspension
    31 ⚠ 1
  5. 05 Fuel System
    22 ⚠ 1

Top Reported Issues

Electrical (63 complaints)
Engine (41 complaints)
Powertrain (35 complaints)
Source: NHTSA (nhtsa.gov) · 2026-03

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Known Problems and Issues +

A total of 70 weaknesses have been documented for the Mercedes-Benz S-Klasse W221 (2005–2013) — 64 engine-related and 6 vehicle-related. 8 problem engines: OM651DE22 (2.1L Diesel), M272 (3.0-3.5L V6), M273 (5.0-5.5L V8), OM642 (3.0L V6 Diesel), M156 (6.2L V8 AMG), M157 (5.5L V8 BiTurbo), M275 (5.5L V12 BiTurbo), OM629 (4.0L V8 CDI). Typical issues affect Suspension, Electronics.

S-Klasse (OM642, 2006–2013) — Stay Away!: Oil Cooler Gaskets Leaking — Oil and Coolant Loss, Swirl Flap Linkage Breaks — Plastic Joint Fails, Injector Seal Leaking — Soot Deposits and Diesel in Oil. Power: 235 PS.

S-Klasse (OM629, 2006–2009) — Stay Away!: Cylinder head warped -- coolant loss, NAG2 transmission at torque limit, Oil Cooler Leak in V-Section. Power: 320 PS.

S-Klasse (OM642, 2010–2013) — Stay Away!: Oil Cooler Gaskets Leaking — Oil and Coolant Loss, Swirl Flap Linkage Breaks — Plastic Joint Fails, Injector Seal Leaking — Soot Deposits and Diesel in Oil. Power: 252–258 PS.

S-Klasse (OM651DE22, 2011–2013) — Stay Away!: Chain Tensioner Seal Leaking — Recall, Timing Chain Stretch (Simplex Chain), Piezo Injector Faults. Power: 204 PS.

S-Klasse (M272, 2005–2013) — Stay Away!: Balance Shaft Sprocket Wears Prematurely, Timing Chain Stretches and Damages Timing, Camshaft Adjuster Leaks — Wiring Harness Contaminated. Power: 272–279 PS.

S-Klasse (M273, 2005–2013) — Stay Away!: Balance shaft sprocket — same weakness as M272, Camshaft Adjuster Leaking — Oil in Wiring Harness, Valve cover gaskets leaking on both sides. Power: 387 PS.

S-Klasse (M275, 2005–2013) — Stay Away!: Ignition module bank failure (two banks at ~€1,400 each), Turbocharger wear and wastegate wear, ABC hydraulic lines and engine mounts — double defect. Power: 517 PS.

S-Klasse (M273, 2006–2010) — Stay Away!: Balance shaft sprocket — same weakness as M272, Camshaft Adjuster Leaking — Oil in Wiring Harness, Valve cover gaskets leaking on both sides. Power: 340 PS.

S-Klasse (M156, 2006–2010) — Stay Away!: Head Bolt Corrosion — Coolant in Combustion Chamber, Camshaft Wear — Cold-Start Lubrication Deficit, Camshaft Adjuster — Locking Plate Wears Out. Power: 525 PS.

S-Klasse (M275, 2006–2013) — Stay Away!: Ignition module bank failure (two banks at ~€1,400 each), Turbocharger wear and wastegate wear, ABC hydraulic lines and engine mounts — double defect. Power: 612 PS.

S-Klasse (M157, 2010–2013) — Stay Away!: Timing Chain Stretch — M157 BiTurbo V8, Oil Consumption from Piston Ring Wear, High-Pressure Fuel Pump Fails — No Fuel Pressure. Power: 544 PS.

What to watch out for with the Mercedes-Benz S-Klasse? See the detailed listing of all engine and vehicle weaknesses in the sections above.

Frequently Asked Questions

What problems and weaknesses does the Mercedes-Benz S-Klasse W221 have? +
The Mercedes-Benz S-Klasse W221 has 64 known engine weaknesses and 6 vehicle weaknesses.
What should I look for when buying a used Mercedes-Benz S-Klasse W221? +
faq.watch_a_avoid
Which engine is recommended? +
None of the available engines are rated 'Good Choice'. Stay away! The most fun to drive is the M275 (5.5L V12 BiTurbo). Problem engine: M157 (5.5L V8 BiTurbo) — stay away!
Which Mercedes-Benz S-Klasse W221 engine is the most fun? +
The {code} ({displacement}) offers the most driving fun in the Mercedes-Benz S-Klasse W221 — rated: "Legendary!". {description} 450 kW, 1,000 Nm, Magic Body Control — the S65 AMG W221 is the ultimate Q-car. Nothing about it betrays what is under the bonnet until full throttle: then 2,150 kg accelerate to 100 in 4.4 seconds without a sound. The V12 does not scream — it surges, silently and brutally. AMG name plate on the engine cover, hand-built in Affalterbach. The price of the maintenance plan should be calculated alongside the purchase price.
Is the Mercedes-Benz S-Klasse W221 worth buying used? +
Caution is advised with the Mercedes-Benz S-Klasse W221 — 8 of 8 engine variants are rated 'Stay Away!'. The engine choice is crucial.
What horsepower variants are available for the Mercedes-Benz S-Klasse W221? +
The Mercedes-Benz S-Klasse W221 is available with engine variants from 120 to 630 hp. Petrol: M272 (3.0-3.5L V6), M273 (5.0-5.5L V8), M156 (6.2L V8 AMG), M157 (5.5L V8 BiTurbo), M275 (5.5L V12 BiTurbo). Diesel: OM651DE22 (2.1L Diesel), OM642 (3.0L V6 Diesel), OM629 (4.0L V8 CDI).

Last updated: February 2026 · All information without guarantee