Mercedes-Benz ML: common faults & what to check

Which Mercedes-Benz ML are you looking at?

3 generation variants documented. Pick the shape you recognise: the faults, the servicing and the timeline below all narrow to it. Free, no account needed.

Engine not documented

3 variants documented

1997–2006W1631997–2006W163Engine not documented for this generationEngine not documentedDocumented issues3 knownSee faults & what to checkPhoto: Elise240SX via Wikimedia Commons, CC BY-SA 4.0.

2005–2012W1642005–2012W164Engine not documented for this generationEngine not documentedDocumented issues5 knownSee faults & what to checkPhoto: OSX via Wikimedia Commons, Public domain.

2011–2019W1662011–2019W166Engine not documented for this generationEngine not documentedDocumented issues1 knownSee faults & what to checkPhoto: EurovisionNim via Wikimedia Commons, CC BY-SA 4.0.

Now narrow it to the engine

A 1.8 and a 2.4 of the same car do not fail the same way, so the faults below narrow to the engine as well as the year. Free, no account needed.

Start your free check on this Mercedes-Benz ML

No plate needed. You get the risk score, the buyer's checklist and the guided inspection for the exact car you picked above — not the whole nameplate.

The checks worth doing on a Mercedes-Benz ML before you hand over any money. Every documented fault is listed below, each with its own page.

• Serious issue

  Check engine serial number against the Mercedes published threshold (below 30468993 on M272).

  See why

  M272/M273 Balance Shaft Sprocket Premature Wear

  The M272 V6 and M273 V8 engines used a composite plastic balance shaft idler gear sprocket that wears prematurely. As teeth degrade, the timing chain slackens and the right-bank camshafts fall out of time. A class action lawsuit was settled by Mercedes-Benz in 2011 for approximately USD $4,000 per affected vehicle. Engines with serial numbers below 30468993 on M272 are most commonly affected, though failures outside this range are also documented.

  What you would notice

  • Cold-start timing chain rattle lasting more than 2–3 seconds
  • Check engine light with P0016 or P0017 camshaft correlation codes
  • Rough idle or misfire at low RPM
  • Metallic debris or swarf in engine oil

  Typically $6,500–$13,000 to put right.

• Costly issue

  Park on level ground overnight and check all four corners for sag in the morning.

  See why

  Airmatic Air Suspension Strut Leak and Compressor Failure

  The W164 Airmatic system is prone to air spring and strut leaks at the upper crimp rings and top seals as rubber perishes with age. The compressor runs excessively to compensate for leaking struts and eventually burns out, often blowing the 40-amp Airmatic fuse. Valve block solenoids also develop internal leaks. Ride height sensor rods become brittle and snap, causing persistent ride height fault messages.

  What you would notice

  • Vehicle sagging at one or more corners after sitting overnight
  • Airmatic malfunction warning on instrument cluster
  • Audible compressor running continuously or repeatedly
  • Uneven ride height or excessively harsh ride

  Typically $1,500–$6,500 to put right.

• Costly issue

  Scan for P2015 fault code before purchase.

  See why

  OM642 Intake Swirl Flap Plastic Linkage Failure

  The OM642 3.0-litre V6 diesel uses plastic actuator linkage rods to control intake manifold swirl flaps. The plastic degrades under heat cycling and breaks, or the swirl flap motor (M55) burns out after EGR carbon buildup stiffens the flap shafts. A failed motor can also drop metal debris into the intake ports, posing risk of engine damage. The failure triggers DTC P2015.

  What you would notice

  • Check engine light with P2015 fault code
  • Power loss and hesitation under acceleration
  • Rough idle especially when cold
  • Excessive black smoke on load

  Typically $650–$2,500 to put right.

• Costly issue

  Inspect beneath the vehicle for oil staining at the transfer case front and rear output seals.

  See why

  W163 Transfer Case Internal Wear and Seal Leaks

  The W163 four-wheel-drive transfer case is prone to internal chain stretch and bearing wear, accelerated by neglected fluid changes. Front and rear output shaft seals are also known to leak, causing oil loss that accelerates internal wear. When the transfer case chain fails, complete replacement is typically necessary. Low-range transfer case motor actuator failure is also documented on W163.

  What you would notice

  • Vibration or shudder at highway speeds
  • Clunking or grinding when engaging 4WD modes
  • Oil puddle visible beneath transfer case
  • Difficulty switching between 2H, 4H, and 4L

  Typically $2,500–$6,500 to put right.

• Costly issue

  Scan for transmission fault codes before purchase.

  See why

  7G-Tronic (722.9) Conductor Plate and Valve Body Failure

  The 722.9 seven-speed automatic transmission uses a solenoid conductor plate embedded in the valve body that is prone to internal failure, particularly on early VGS1-coded units fitted from 2005–2008. Extended service intervals with degraded transmission fluid accelerate solenoid wear. Both the conductor plate and valve body may require replacement together for a lasting repair.

  What you would notice

  • Harsh jolt or hesitation on 1-2 upshift
  • Transmission stuck in second gear (limp home mode)
  • Delayed engagement from park or reverse
  • Transmission warning light or fault codes

  Typically $2,500–$6,000 to put right.

• Costly issue

  Inspect the engine valley between the two cylinder banks for oil residue.

  See why

  OM642 Oil Cooler Rubber Seal Degradation

  The OM642's oil cooler is positioned centrally in the engine V, surrounded by hot intake plumbing that traps heat. The original orange rubber seals degrade prematurely under sustained thermal load, causing oil leaks and potential oil-coolant cross-contamination. Mercedes upgraded to Viton purple seals from approximately 2010, but leaks still occur. Repair requires removal of turbochargers, intake manifolds, and EGR cooler, typically 8–10 workshop hours.

  What you would notice

  • Oil leak residue in the centre valley of the engine
  • Unexplained coolant loss without visible external leak
  • Oil contamination in coolant reservoir
  • Engine oil overconsumption

  Typically $2,500–$5,800 to put right.

What these repairs cost on other cars

Some of the Mercedes-Benz ML’s documented faults are repairs other models share. Each page lists the documented NZ cost for every model it affects.

• Diesel Injector Replacement Cost
• Turbo Repair and Replacement Cost

Other Mercedes-Benz models