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Mercedes-Benz E-Class: W211 M272/M273 V6/V8 Balance Shaft Sprocket Plastic Tooth Failure

W211 M272/M273 V6/V8 Balance Shaft Sprocket Plastic Tooth Failure is a very common engine fault on the Mercedes-Benz E-Class on the 2004–2007 cars, and we rate it critical. Putting it right costs ≈A$3,220 to ≈A$8,280 at independent workshop rates, shown as an approximate guide in Australian dollars. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 26 documented faults on the Mercedes-Benz E-Class.

Vehicle
Mercedes-Benz E-Class
Engine
2.5L / 3.0L / 3.5L / 4.7L / 5.5L
Years
2004–2007
Fuel
petrol
System
Engine

This page covers the Mercedes-Benz E-Class as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Mercedes-Benz E-Class faults26 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Timing chain yet. We would rather show none than show a picture of a different part.

What goes wrong

The M272 (3.0/3.5 V6) and M273 (5.0 V8) engines in the W211 E-Class suffer from a widely documented failure of the balance shaft module sprocket. The sprocket uses plastic composite teeth that wear and strip progressively, causing balance shaft desynchronisation from the crankshaft. This results in rough running, timing chain wear, and in advanced cases complete engine destruction. Mercedes faced class action proceedings in Australia over this issue and issued extended warranty coverage. All W211 E-Class petrol models should be considered at risk unless documented repair is verified.

What you would notice

  • Rough idle that progressively worsens
  • Check engine light with camshaft position or balance shaft correlation codes
  • Rattling from engine at idle or low RPM
  • Loss of power and increased fuel consumption

How to check it

Where to look. Front of engine block, balance shaft module and drive sprocket within timing chain circuit

This is the highest priority check on any W211 petrol. Scan ECU for camshaft correlation codes and balance shaft faults. Cold-start and listen for timing chain rattle. Check service records for documented balance shaft sprocket replacement — it is a specific, significant repair. Vehicles with absent or unverified history should be treated as unrepaired.

Parts involved: Timing chain.

What it costs to put right

≈A$3,220 to ≈A$8,280 at independent workshop rates, shown as an approximate guide in Australian dollars. That is for this job on its own, not for the car.

An estimate, converted to Australian dollars, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

  • “Has the balance shaft sprocket been replaced?”
  • “Was the Mercedes warranty or service campaign completed for this engine?”
  • “Has the engine had any rebuild or timing chain work?”

Now check the Mercedes-Benz E-Class you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car still has money owing on it, has been written off or reported stolen, what kms it showed in past sale ads, whether it has had accident repair claims and what it is worth today. That comes from the official records for that plate. Enter the plate and its state for the A$17.90 Vehicle Check, or the full history from A$24.99.

Where this comes from

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.

Mercedes-Benz E-Class buyer questions

Is w211 m272/m273 v6/v8 balance shaft sprocket plastic tooth failure serious on a Mercedes-Benz E-Class?

We rate it critical and very common on the Mercedes-Benz E-Class. The M272 (3.0/3.5 V6) and M273 (5.0 V8) engines in the W211 E-Class suffer from a widely documented failure of the balance shaft module sprocket. The sprocket uses plastic composite teeth that wear and strip progressively, causing balance shaft desynchronisation from the crankshaft. This results in rough running, timing chain wear, and in advanced cases complete engine destruction. Mercedes faced class action proceedings in Australia over this issue and issued extended warranty coverage. All W211 E-Class petrol models should be considered at risk unless documented repair is verified.

How much does it cost to fix on a Mercedes-Benz E-Class?

≈A$3,220 to ≈A$8,280 at independent workshop rates, shown as an approximate guide in Australian dollars. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Mercedes-Benz E-Class years are affected?

Our research records this fault on the 2004–2007 Mercedes-Benz E-Class. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.

How do I check for it before I buy?

This is the highest priority check on any W211 petrol. Scan ECU for camshaft correlation codes and balance shaft faults. Cold-start and listen for timing chain rattle. Check service records for documented balance shaft sprocket replacement — it is a specific, significant repair. Vehicles with absent or unverified history should be treated as unrepaired. Look here: Front of engine block, balance shaft module and drive sprocket within timing chain circuit