Air suspension (Airmatic)
usually 100,000–200,000 km · Medium risk
Signs: Car sits low, compressor runs long
Fix: Replace strut / compressor
€700–2,200
Common faults, service intervals and costs
Mercedes-Benz R-Class (W251)
2005–2013
2
engines covered
9
known faults
2,137
roadworthiness tests in the statistics
Enter your VIN and mileage and get a plan built for your exact engine and gearbox.
The Mercedes-Benz R-Class (W251) was built from 2005 to 2013.
For this generation we cover 2 engines and 9 known faults, each with the mileage range where it usually appears.
The most expensive known risk is Balance shaft / idler sprocket wear (pre-2008): it usually appears at 80,000–180,000 km and costs €2,500–5,000 to fix.
In UK roadworthiness tests in 2024, at 150–200 thousand km this model most often failed on: lights, wipers and visibility (13.8 %), brakes (11.3 %), exhaust, emissions and leaks (6.1 %). It fails less often than average on: suspension, steering, tyres and wheels, lights, wipers and visibility, body and corrosion.
Engines
| Engine | Fuel | Timing drive | Oil |
|---|---|---|---|
| 3.0 CDI V6 (Mercedes OM642) | Diesel | Chain | 5W-30 · MB 229.51 · ~8.0 L · every 15,000 km |
| 2.5 / 3.0 / 3.5 V6 & V8 (Mercedes M272 / M273) | Petrol | Chain | 5W-30 / 5W-40 · MB 229.5 · ~8.0 L · every 15,000 km |
Faults typical of this model
Faults by engine
3.0 CDI V6 (Mercedes OM642)
Oil cooler seals (engine valley)
usually 120,000–220,000 km · High risk
Signs: Oil leak at the back of the engine / bellhousing
Fix: Reseal the oil cooler (intake off)
€1,000–2,000
Intake swirl flaps / actuator
usually 120,000–220,000 km · Medium risk
Signs: Engine light, limp mode
Fix: Replace manifold or actuator
€600–1,500
EGR / DPF
usually 150,000–250,000 km · Medium risk
Signs: Limp mode
Fix: Clean or replace
€400–1,800
Timing chain guides (early engines)
usually 150,000–250,000 km · Medium risk
model years 2005–2010 only
Signs: Rattle
Fix: Replace guides and chain
€1,500–3,000
2.5 / 3.0 / 3.5 V6 & V8 (Mercedes M272 / M273)
Balance shaft / idler sprocket wear (pre-2008)
usually 80,000–180,000 km · High risk
model years 2004–2008 only
Signs: Engine light P0016 / P0017, rattle
Fix: Replace sprocket and chain
€2,500–5,000
Intake manifold flap failure
usually 100,000–200,000 km · Medium risk
Signs: Engine light, power loss
Fix: Replace intake manifold
€500–1,200
Thermostat / coolant leaks
usually 100,000–200,000 km · Wear part
Signs: Slow warm-up, coolant loss
Fix: Replace thermostat
€150–400
Gearboxes
5G / 7G / 9G-Tronic
Conductor plate / speed sensor (5G / 7G-Tronic)
usually 100,000–220,000 km · Medium risk
Signs: Stuck in gear, limp mode, harsh shifts
Fix: Replace the conductor plate; fluid every 60–100,000 km
€500–1,500
Scheduled service
Intervals and typical prices for the 3.0 CDI V6 (Mercedes OM642) engine. Other engines differ in oil, timing drive and some filters; the app gives the exact plan.
| Item | Interval | Typical price |
|---|---|---|
| Engine oil + oil filterEngine | every 15,000 km or every 12 months | €70–150 |
| Cabin (pollen) filterClimate | every 15,000 km or every 12 months | €15–40 |
| Brake fluidBrakes | every 24 months | €50–95 |
| A/C service (regas + desiccant)Climate | every 24 months | €70–150 |
| Air filterEngine | every 30,000 km or every 24 months | €15–45 |
| Fuel filterFuel | every 30,000 km or every 24 months | €40–110 |
| Automatic transmission fluidTransmission | every 90,000 km | €200–450 |
| Glow plugsEngine | every 100,000 km | €120–300 |
| Auxiliary (serpentine) beltEngine | every 120,000 km | €70–180 |
| Coolant replacementCooling | every 150,000 km or every 96 months | €70–150 |
| Timing chain inspection (listen on cold start)Engine | every 150,000 km | €0–120 |
| Front brake padsBrakes | usually at 30,000–60,000 km | €60–150 |
| Front brake discs + padsBrakes | usually at 60,000–120,000 km | €150–320 |
| Rear brake padsBrakes | usually at 50,000–90,000 km | €50–130 |
| Tyres (set of 4)Wheels | usually at 40,000–60,000 km | €320–700 |
| Wiper bladesBody | checked at service | €20–50 |
| 12V batteryElectrical | checked at service | €100–220 |
Roadworthiness tests by mileage
Share of tests in the United Kingdom (DVSA MOT, 2024) that this model failed because of each system. Bold red means more often and green less often than an average car of the same age and mileage. Sample: 2,137 tests.
| thousand km | 150–200 | 200–250 |
|---|---|---|
| Brakes | 11.3 % | 13.3 % |
| Suspension | 5.4 % | 5.3 % |
| Steering | 1.2 % | 1.6 % |
| Tyres and wheels | 5.4 % | 6.7 % |
| Lights, wipers and visibility | 13.8 % | 15.5 % |
| Body and corrosion | 5.1 % | 7.4 % |
| Exhaust, emissions and leaks | 6.1 % | 7.2 % |
Most common engine versions in the EU
New cars of this generation registered in the EU, Iceland and Norway 2010–2025: 7,528, of which 0 in Croatia. The share shows how common each version is.
| Version | Share | Years | CO₂ | Fuel use |
|---|---|---|---|---|
| 3.0 CDI V6 (Mercedes OM642)3.0 (2,987 cm³) · Diesel | 60.4 % | 2010–2013 | — | — |
| 3.0 CDI V6 (Mercedes OM642)3.0 (2,987 cm³) · 195 kW (265 hp) · Diesel | 27.6 % | 2011–2013 | — | — |
| 3.0 CDI V6 (Mercedes OM642)3.0 (2,987 cm³) · 140 kW (190 hp) · Diesel | 4.8 % | 2011–2013 | — | — |
| 3.0 CDI V6 (Mercedes OM642)3.0 (2,987 cm³) · 155 kW (211 hp) · Diesel | 1.8 % | 2011–2013 | — | — |
| 2.5 / 3.0 / 3.5 V6 & V8 (Mercedes M272 / M273)3.5 (3,498 cm³) · Petrol | 1.7 % | 2010–2012 | — | — |
Source: European Environment Agency (EEA), monitoring of CO₂ emissions from new passenger cars, CC BY 4.0. CO₂ and fuel use are official type-approval values (WLTP from 2021), not real-world consumption.
Owner complaints in the US
Which systems owners reported to the US agency NHTSA and at what mileage. Complaints are not confirmed faults and some relate to recalls. Sample: 219 complaints.
Common questions
Does the Mercedes-Benz R-Class (W251) have a timing chain or a timing belt?
3.0 CDI V6 (Mercedes OM642): chain; 2.5 / 3.0 / 3.5 V6 & V8 (Mercedes M272 / M273): chain.
What are the known problems with the Mercedes-Benz R-Class (W251)?
The faults with the highest risk: balance shaft / idler sprocket wear (pre-2008) (80,000–180,000 km, €2,500–5,000); oil cooler seals (engine valley) (120,000–220,000 km, €1,000–2,000); timing chain guides (early engines) (150,000–250,000 km, €1,500–3,000); air suspension (Airmatic) (100,000–200,000 km, €700–2,200). The full list by engine is on this page.
What does the Mercedes-Benz R-Class (W251) most often fail its roadworthiness test on?
In UK roadworthiness tests in 2024, at 150–200 thousand km this model most often failed on: lights, wipers and visibility (13.8 %), brakes (11.3 %), exhaust, emissions and leaks (6.1 %). It fails less often than average on: suspension, steering, tyres and wheels, lights, wipers and visibility, body and corrosion.
What should you check when buying a used Mercedes-Benz R-Class (W251)?
Before you buy, ask an authorised dealer to check by VIN whether the car has any open recalls. On the test drive, watch for these signs: engine light P0016 / P0017, rattle; oil leak at the back of the engine / bellhousing. The full checklist is in the guide to buying a used car.
Models with the same engines
These models share engines with this car, so they share some of its faults too.
Mercedes-Benz C-Class (W204) 2007–2014Mercedes-Benz E-Class (W212) 2009–2016Mercedes-Benz C-Class (W203) 2000–2007Mercedes-Benz E-Class (W211) 2002–2009Mercedes-Benz ML / GLE (W166) 2011–2019Mercedes-Benz Sprinter (906) 2006–2018Mercedes-Benz Vito (W639) 2003–2014Mercedes-Benz GLK (X204) 2008–2015
Other Mercedes-Benz models
Mercedes-Benz B-Class (W245) 2005–2011Mercedes-Benz ML (W164) 2005–2011Mercedes-Benz S-Class (W221) 2005–2013Mercedes-Benz A-Class (W169) 2004–2012Mercedes-Benz CLS (C219) 2004–2010Mercedes-Benz GL (X164) 2006–2012Mercedes-Benz SLK (R171) 2004–2011Mercedes-Benz CLK (C209) 2002–2010Mercedes-Benz SL (R230) 2001–2011Mercedes-Benz B-Class (W246) 2011–2018
Sources and notes
Faults, intervals and prices are indicative and collected from public sources and owner experience; always rely on the service book and a qualified workshop. Test statistics: DVSA – Anonymised MOT tests and results, Open Government Licence v3.0. Dutch tests: RDW Open Data (CC0). Engine versions: EEA, monitoring of CO₂ emissions from new passenger cars (CC BY 4.0, DG CLIMA). Owner complaints: NHTSA ODI (public domain). Recalls: DVSA Vehicle Safety Branch Recalls Database, OGL v3.0. Brand and model names are trademarks of their owners and are used only to describe the vehicles.
Updated 08/10/2026