Both are Mercedes V6 petrol engines, but the M272 (3.5‑litre, 2004–2011) and the M276 (3.0‑litre, 2011+) are not interchangeable. This guide shows you exactly how to identify which engine is in your car, which chassis they fit, and why getting it right matters for replacement.
The M272 and M276 are both Mercedes V6 petrol engines, but they are not interchangeable. The M272 is a 3.5‑litre unit (2004–2011) with a known balance‑shaft issue, while the M276 is a 3.0‑litre unit (2011+) with a different timing chain design and improved reliability. To identify which you have, check the engine code label on the timing cover or decode the 8th character of your VIN – for M272 it's typically "M" (for early models) and for M276 it's "276" in the engine number.
If you're unsure which engine is in your Mercedes, this guide will walk you through every identification step.
This table shows which Mercedes models and chassis each engine was factory‑fitted to. The M272 and M276 belong to different generations and are not physically or electronically interchangeable.
| Engine | Displacement | Chassis Codes | Key Models | Production Years |
|---|---|---|---|---|
| M272 | 3.5 V6 (3498 cc) | W203, W204, W211, W164, X204, C219, R171, W221 (early) | C‑Class, E‑Class, ML, GLK, CLS, SLK, S‑Class | 2004–2011 |
| M276 | 3.0 V6 (2996 cc) | W212, W213, W166, C218, X166, W221 (late), W222, V167 | E‑Class, CLS, GLE, GLS, S‑Class, GLE | 2011–present |
Important: While both are V6 petrols, they have different engine mounts, ECU pinouts, and timing chain configurations. Fitting an M272 into a chassis designed for an M276 (or vice versa) is not a simple swap – it requires extensive modification and is rarely cost‑effective.
For a complete overview of all Mercedes engine fitments, see the full fitment matrix.
There are three reliable methods to confirm whether you have the M272 or M276. Use the one that suits your situation.
Open the bonnet and locate the sticker on the timing cover or camshaft cover. For an M272, the code will be clearly marked as M272 (e.g., M272 E35). For the M276, you'll see M276 (e.g., M276 DE30). This is the most direct method.
The 8th character of your VIN can indicate the engine family. For M272, it's often a letter like "M" (early) or "9" (later). For M276, the engine number itself contains "276". Use our free Mercedes VIN decoder for a full breakdown.
The V5C logbook includes the engine number, which typically starts with the engine code (e.g., 272... or 276...). Cross‑reference with our Engine Code Guide.
If you cannot locate the code, a vetted Mercedes specialist can identify it during a service.
For exact locations and photos, see the engine number location guide.
Installing the wrong engine is one of the most expensive mistakes you can make. Here's why getting the code right is critical:
Once you've confirmed the engine, you can check replacement costs and use the repair vs. replace calculator to make an informed decision.
The M272 and M276 are often confused with other Mercedes engines. Avoid these pitfalls:
If you're still unsure, use the OM vs. M‑series identification guide or contact a specialist.
The easiest way is to check the 8th character of your VIN. Use our VIN decoder to get a full breakdown. You can also look at the V5C logbook – the engine number will start with "272" or "276".
The M276 is generally considered more reliable. The M272 has a well‑known balance‑shaft issue (timing chain sprocket wear) that can be catastrophic. The M276 revised the design and is less prone to this failure. However, the M276 can suffer from camshaft adjuster wear and oil leaks. See the M272 Knowledge Centre and M276 Knowledge Centre for full reliability verdicts.
No – the engine mounts, ECU, wiring, and ancillaries are different. It is not a practical DIY swap and would cost more than simply replacing with the correct engine. Always replace like‑for‑like.
Supply‑only costs are similar: a reconditioned M272 is around £3,800–£6,500, and an M276 is also £3,800–£6,500 [EM‑QUOTE]. Labour for R&R is typically 12–16 hours, adding £780–£1,040 at independent rates. See the replacement cost guide for full details.
If the cost of a replacement engine (supply + fitting) exceeds approximately 70% of your car's current market value, it may be more economical to scrap the car. For an older E‑Class W211 with an M272, the threshold is often reached; for a newer W213 with an M276, replacement is usually viable. See the repair/replace/scrap framework for worked examples.
Knowing whether you have an M272 or M276 is the first and most important step before any engine work. Use the methods above – engine code label, VIN decoder, or V5C – to confirm which V6 petrol you have. Then cross‑check the fitment matrix to ensure the engine matches your chassis.
Once identified, you can assess the repair or replacement cost. If your engine has failed, compare the reconditioned cost against your vehicle's value using the repair vs. replace calculator. Always use a vetted Mercedes specialist for the work.
Check Your Engine with Registration LookupReady to identify your engine or get a quote? Compare prices from vetted Mercedes specialists.