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Mercedes-Benz GL-Class GL 500 4Matic common faults.

2012–2015, SUV, petrol, 435 HP.

The fault list covers: M278DE46AL engine, MB7229, MB7250 transmission.

What you save stays on this device only. My saves

5 fault write-ups. All are important. 7 recalls.

If you know the year, pick it. Faults for other years drop out of the list.

Before you buy

Known faults

5 important faults

critical1

M271, M272, M273: a leaking camshaft adjuster magnet and oil in the wiring harness

critical

The solenoid of the camshaft adjuster is sealed from the factory by nothing more than a plain sealing ring, and over time that starts to leak. The maker's own bulletin names two places: if the leak is between the solenoid and the cylinder head, the sealing ring has to be replaced, and if it comes through the electrical connector, then the solenoid itself.

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The more serious trouble is at the connector. Through it the engine oil gets into the engine wiring harness and travels under the insulation by capillary action, so it reaches the engine control unit and other important parts as well. The loss of the control unit is the end of that road, and serious engine damage can follow; alongside the contaminated harness the most varied fault messages can appear. Cases have been reported where the oil ran out of the connector, and the consequential damage after that was already large.

The check is simple: the connector of the solenoid has to be taken off and looked at to see whether it is oily. In the fault memory a faulty solenoid gives one of the codes 0059, 0060, 0063, 0064, 0271, 0272, 0275 and 0276. One thing is worth knowing: according to the maker only the solenoid that has a corresponding code has to be replaced, so if a workshop has changed all four of them alongside two codes, that is worth asking about.

The engine number decides what is in the car. Above engine number 2729..30 759427 (M272) and 2739..30 193592 (M273) the maker already fitted the improved solenoid, under part number A272 051 01 77. The oil-leaking solenoid is a problem on engine numbers below 2729..30 895140 and 2739..30 236360.

The prevention is the oil stop cable, which has to be fitted between the solenoid and the harness: the two wires contain a sealed copper sleeve covered with heat-shrink tubing, and that stops the oil from travelling further. It is available from the factory and is not expensive: the two solenoids were around 33 euros and the two oil stop cables around 31 euros, while replacing the control unit is a four-figure sum.

between 90,000 and 130,000 kmfrom 31 EUR

What to check

  • Ask whether an oil stop cable has been fitted between the camshaft solenoids and the harness
  • Ask for a check: taking the connector off the solenoid shows whether it is oily
  • Read the fault memory and look for codes 0059, 0060, 0063, 0064, 0271, 0272, 0275 and 0276
3 more steps in the write-up

expensive4

Chain tensioner: the check valve is missing from the oil supply

expensive

The check valve is missing from the oil supply of the timing chain tensioner. With the engine stopped the oil drains out of the passage, so at start-up the tensioner does not get pressure straight away, and over time that wears it out. On early production examples it appears from as little as 60 000 kilometres.

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The tensioner does not hold the chain, the chain goes slack and the valve timing shifts. The symptom is a metallic rattle audible at a cold start which quietens after a few seconds. If the chain jumps, the valves and the pistons meet.

The same noise is also produced by a failure of the camshaft adjuster, and there the fault code gives the direction: P001685, P001785, P001177 and P001885 belong to it.

The repair is not an engine strip. The tensioner can be reached after the charge air cooler and the front cover have been removed, and from there two screws hold it. The prevention is fitting the check valve into the oil supply.

above 60,000 km

What to check

  • Start it cold and listen to the first seconds: a metallic rattle points here
  • Watch whether the noise quietens after a few seconds: that is typical of the tensioner
  • Have the fault codes read and look for codes P001685, P001785, P001177 and P001885
1 more steps in the write-up

7G-Tronic (722.9): mechatronics and conductor plate

expensive

In the Mercedes 7 speed 722.9 automatic (7G-Tronic / 7G-Tronic Plus) the mechatronics unit and the conductor plate (Leiterplatte) age over time: jerking on shifts, delayed engagement, a "Getriebe schützen" message, and fault codes on the gearbox electronics.

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The repair is typically replacing the mechatronics unit or the conductor plate together with an oil change: not the whole gearbox. The complaint is most common on the longitudinal platforms from around 2005 to 2015 (C/E/ML and the early GLC).

The 9G-Tronic (725.0) is a different design; this applies only to the 7G.

between 100,000 and 220,000 km

What to check

  • Try it cold and warm: a delayed 1 to 2 or 2 to 3 shift is suspect
  • Watch for the gearbox warning or the "Getriebe schützen" message on the dash
  • Ask for a fault code read on the gearbox controller (not just the engine codes)
1 more steps in the write-up

Airmatic air suspension: leaking air spring, overworked compressor

expensive

The Mercedes Airmatic system holds the ride height with air springs and electronically controlled dampers. The most common faults over time are the relay, the compressor and a leaking air spring or air line.

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The rear air springs of the 2003 to 2009 E-Class (W211) are particularly prone to leaking along the clamps. If the system leaks, the compressor runs continuously, overheats and fails, so an unrepaired leak takes the compressor with it.

Symptoms: one corner of the car sinks by morning, an "Air Suspension" or level control fault message, and compressor noise while standing. It was an option (or standard) across several generations from the W220 S-Class onwards; the estate E-Class often has air springs with level control on the rear axle as standard.

between 100,000 and 220,000 km

What to check

  • In the morning, before setting off, look at all four corners: an uneven stance means a suspected leak
  • With the car standing, listen to the compressor: continuous running indicates it is overworked
  • Ask for a fault code read on the suspension controller (level and pressure sensor codes of the C1132 / C1144 kind)
3 more steps in the write-up

Silitec cylinder liner: detonation eats it away, and the engine number decides

expensive

The cylinder wall is formed by a Silitec liner: an aluminium-silicon alloy which the maker cast into the aluminium cylinder in order to reduce friction, heat and wear. This material, however, could not cope with the high temperature and the occasional detonation of this engine.

Show the rest

On a damaged liner the cylinder wall becomes scored, and from then on the piston ring no longer seals: oil consumption rises and compression falls. The same material also wore the valve guides seriously. The maker finally switched to the Nanoslide coating, precisely because of Silitec's cylinder scoring problems.

It is not the mileage that marks out the affected cars but the engine number. Into engines above 2789xx 30 266191 the maker already fitted cast-in iron liners, which means that from there on this failure mode does not exist. It is reported on examples with an engine number below that, typically above 120 000 kilometres.

The symptom is blue smoke, rising oil consumption and uneven running. The repair is machining or replacing the block, which makes this the most expensive failure on this engine.

above 120,000 km

What to check

  • Check the engine number: engines above 2789xx 30 266191 already have iron liners
  • Ask how much oil has to be topped up between changes
  • Watch the exhaust when the revs are blipped: blue smoke means oil burning
2 more steps in the write-up

Checklist

Mercedes-Benz GL-Class GL 500 4Matic

First what you would check on any car. Then the faults of this model.

Before you buy

Checklist

The printed sheet starts with what you would check on any car. What you tick stays on this device only.

On every car

Ask the owner

Faults of this model

vinkodex.com · Before you buy it, see what can go wrong.

Official recall7 recallsShow

The manufacturer fixes these for free at a franchised dealer. Ask with the VIN whether it was done.

A12/0069/17Safety recallInjuriesno date · EU Safety Gate

Due to incorrect functioning of the occupancy sensor system on the passenger's side, the airbag may not deploy in the event of an accident.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

We could not check this: model year. The authority's notice

A12/00830/22Safety recallInjuriesno date · EU Safety Gate

Severe corrosion may lead to a leakage of the brake booster, thus reducing the braking force, leading to an increase in brake pedal force required to decelerate the vehicle, resulting in a possible increase in stopping distance. Moreover, due to severe corrosion, a particularly strong or severe braking manoeuvre may cause mechanical damage to the brake booster, preventing the vehicle from decelerating through the service brake and thus increasing the risk of an accident. The product does not comply with the requirements laid down in the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

We could not check this: model year. The authority's notice

A12/01236/20Safety recallInjuriesno date · EU Safety Gate

The driver and passenger airbags of the company Takata in vehicles with ammonium nitrate gas generators without drying agents could, under certain climate conditions, lead over time to a chemical change in the fuel. In the event of an accident triggering the release of the driver or passenger airbag, this change could cause the gas generators to burst. If a gas generator ruptures, the airbag would then have no restraining function and loose parts from the gas generator could reach the vehicle interior. This would increase the risk of injury for passengers.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

We could not check this: model year. The authority's notice

A12/0286/17Safety recallInjuriesno date · EU Safety Gate

The upper suspension arm may not have been correctly screwed to the stub axle, which could affect the steering.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

We could not check this: model year. The authority's notice

A12/0457/17Safety recallInjuriesno date · EU Safety Gate

Following the update of the control unit coding, the coding parameters of the control unit could be defective. This could give rise to various unplanned reactions in the vehicle: the wrong airbag could be triggered in the event of an accident, the airbag control unit may not recognise the belt buckle status, the engine control unit could be coded with a false maximum speed or various assistance systems may not function.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

We could not check this: model year. The authority's notice

A12/1385/18Safety recallFireno date · EU Safety Gate

The sealing cap of the Active Curve System's oil reservoir does not prevent oil from leaking out. Oil may leak out and spray onto hot components. As a consequence it may ignite and lead to fire.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

We could not check this: model year. The authority's notice

SR/03711/24Safety recallInjuriesno date · EU Safety Gate

The three aluminium screws of the steering box may corrode due to exposure to spray water and aggressive road-grit (salt) used for melting ice. Advanced corrosion could weaken the screws, leading to potential breakage during manoeuvring or parking. If all fixing screws fail, the power-assisted steering could detach, resulting in a loss of power steering and an increased risk of an accident. The product does not comply with the Regulation on the approval and market surveillance of motor vehicles and their trailers, and of systems, components and separate technical units intended for such vehicles.

Remedy: Type of economic operator taking notified measure(s): Manufacturer Category of measure(s): Recall of the product from end users Date of entry into force: Unknown

We could not check this: model year. The authority's notice

Engine and transmission

1 engines · 2 transmissions

M278DE46AL

320–335 kW (435–455 HP) · petrol

MB7229 · 7G-Tronic / 7G-Tronic Plus, longitudinal (Mercedes 722.9 / NAG2)

automatic · 7 speed

Torque limit700 Nm
MakerMercedes-Benz

We built the code from the model and the gear count. The factory sheet does not state it. More than one transmission is possible. 7 gears = MB7229, 9 gears = MB7250.

Variant data

What is in this version

Factory data

Trim
GL 500 4Matic
Body
SUV
Fuel
petrol
Transmission
automatic
Engine size
4663 cc
Power
320 kW (435 HP)
Drive
AWD
Production
2012–2015

Factory service interval

The manufacturer specifies this for this version. Of the mileage and the time, the one that comes first is the one that counts.

  • Air filter

    • 60,000 km or 4 years

  • Cabin (pollen) filter

    • 30,000 km or 2 years

  • Brake fluid change

    • first: 3 years, then 2 years(first change at 3 years, then every two years)

  • Spark plugs, petrol

    • 60,000 km or 6 years
All X166 versions

Information, not an expert opinion

We write the descriptions, and we put the source next to them. A person reviews them before they go out. They are still information, not a technical expert opinion.

  • A fault on the list does not mean the car you are looking at has it.
  • A fault missing from the list does not mean the model is fault-free. Write-ups are made model by model. Not all of them are done.
  • You decide whether to buy. This is no substitute for an inspection. That needs a workshop and a history check.
Details in the terms