Every Mercedes engine code, every chassis, every generation. Use this index to confirm fitment, identify your engine, or check compatibility for a replacement. Data-backed by 9,000+ UK enquiries and verified by our specialist network.
Mercedes engine fitment is chassis-specific: each model and generation uses a defined set of engine codes. The wrong engine won't fit, won't talk to the ECU, and won't pass MOT. This index lists every engine family, the chassis it fits, and the link to your model page.
Use this index to look up your engine or find which engines fit your chassis. Then confirm with your VIN and a specialist.
The table below lists every major Mercedes engine family, the chassis codes it was fitted to, and the models you'll find it in. Use this as your starting point for any fitment query. For a full breakdown of which engines fit which cars, see the complete fitment matrix.
| Engine Code | Engine Type | Chassis Codes | Key Models |
|---|---|---|---|
| OM651 | 2.1 Diesel | W204, W205, W212, W213, X204, X253, W447, W906 | C-Class, E-Class, GLC, GLK, Sprinter, V-Class |
| OM654 | 2.0 Diesel | W205, W206, W213, W214, X253, X254, V167 | C-Class, E-Class, GLC, GLE |
| OM642 | 3.0 V6 Diesel | W211, W212, W164, W166, X204, W251, W906 | E-Class, ML/GLE, GLK, R-Class, Sprinter |
| OM646 | 2.1 Diesel | W204, W211, W906 | C-Class, E-Class, Sprinter (pre-2010) |
| OM656 | 2.9 Diesel | W213, W222, W223, V167 | E-Class, S-Class, GLE |
| M276 | 3.0 V6 Petrol | W212, W213, W166, C218, X166 | E-Class, CLS, GLE, GLS |
| M274 | 2.0 Petrol | W205, W213, X253 | C-Class, E-Class, GLC |
| M272 | 3.5 V6 Petrol | W204, W211, W164, X204, C219 | C-Class, E-Class, ML, GLK, CLS |
| M273 | 5.5 V8 Petrol | W211, W221, W164, C216 | E-Class, S-Class, ML, CL |
| M270 | 2.0 Petrol | W176, W246, X156 | A-Class, B-Class, GLA |
| M178 | 4.0 V8 Biturbo | C190, R190, W463, X290 | AMG GT, G-Class, AMG GT 4-Door |
| M177 | 4.0 V8 Biturbo | W205, W213, W222, X166, V167 | C63, E63, S-Class, GLE/GLS AMG |
| M157 | 5.5 V8 Biturbo | W212, W221, W222, X166, C218 | E63, S63, GLE63, CLS63 |
| M156 | 6.2 V8 | W204, W212, X164, W463 | C63, E63, ML63, G63 |
| M111 | 2.0 Petrol | W202, W203, W210 | C-Class, E-Class (pre-2005) |
| M112 | 2.8/3.2 V6 | W203, W210, W211, W163 | C-Class, E-Class, ML |
| M113 | 5.0 V8 | W211, W220, W163, R230 | E-Class, S-Class, ML, SL |
| M104 | 2.8/3.2 Inline-6 | W124, W140, R129 | E-Class, S-Class, SL (1990s) |
| M103 | 3.0 Inline-6 | W124, W126 | E-Class, S-Class (1980s) |
| M102 | 2.0/2.3 Petrol | W201, W124 | 190E, E-Class |
| M120 | 6.0 V12 | W140, R129 | S600, SL600 |
| M275 / M279 | 5.5/6.0 V12 | W220, W221, C216, R230 | S600, CL600, SL600 |
| OM617 | 3.0 Diesel | W123, W126, G-Class | E-Class, S-Class, G-Class (1980s) |
| OM611 | 2.2 Diesel | W203, W211, W906 | C-Class, E-Class, Sprinter |
| OM640 | 2.0 Diesel | W168, W169, W245, W414 | A-Class, B-Class, Vaneo |
This table is updated with 2025 enquiry data [EM-VERIFIED]. For the latest fitment details on your specific model, use the links above or visit the full fitment matrix.
Whether you're replacing a failed engine, upgrading, or confirming what's in your car, this index helps you narrow it down in three steps.
Check the label on the timing cover or cylinder head. For M-class petrol, look for M272 or M276. For OM-series diesel, OM651 or OM642. If you're unsure, use our Mercedes VIN decoder — the 8th character of your VIN often tells you the engine family.
Look up your engine code in the table above. The chassis codes column tells you which models and generations it was factory-fitted to. For example, OM651 appears in W204, W205, W212, W213, X253 — that's C-Class, E-Class, and GLC across multiple generations.
Once you know the engine and chassis, check the fitment matrix for detailed variants (e.g., OM651 DE22 LA vs. OM651 DE22 LA EVO). Then see the replacement cost guide to understand what a reconditioned unit will cost you.
If you need a visual guide, the engine number location page shows where to find the code on the engine block.
Based on 9,000+ UK enquiries in 2025, these are the most frequently queried engine-chassis combinations [EM-VERIFIED].
1,250 requests in 2025 — the most common diesel Mercedes engine. Fitted to the W204 (2007-2014) and W205 (2014-2021) C-Class. Also appears in the E-Class W212/W213 and GLC X253.
OM651 Knowledge Centre OM651 Balance Shaft Failure880 requests in 2025 — the 3.0 V6 diesel. Most common in the W211 (2003-2009) and W212 (2009-2016) E-Class. Also in the ML/GLE W164/W166 and Sprinter W906.
OM642 Knowledge Centre OM642 Swirl Flap Failure390 requests in 2025 — the 3.0 V6 petrol. Found in the W212 E-Class and C218 CLS, as well as the GLE W166. Petrol Ingenium equivalent in the Mercedes range.
M276 Knowledge Centre M276 Camshaft Adjuster Failure520 requests in 2025 — the newer 2.0 diesel. Successor to OM651, fitted to the W213 E-Class (2016+) and X253 GLC (2015+). Considerably more reliable than its predecessor.
OM654 Knowledge Centre OM654 Injector Seal FailureFor a full ranking of enquiry volumes by engine, see the Engine Failure Index 2026.
Getting the engine code right is the single most important step before ordering a replacement or checking compatibility. Here's how to find it.
The engine code is stamped on a metal plate or machined surface on the cylinder block. For OM651, it's on the left side of the block near the oil filter housing. For M276, it's on the front of the block behind the intake manifold. The engine number location page has diagrams for every family.
Most Mercedes engines have a sticker on the timing cover or camshaft cover with the engine code and other details. This is the easiest place to check without lifting the car.
The 8th character of your VIN often indicates the engine family. For example, a VIN with the 8th character "9" usually means an OM651 diesel. Use our Mercedes VIN decoder for a full breakdown.
The V5C logbook includes the engine number. Cross-reference that with the engine code list in our Engine Code Guide.
If you're still unsure, contact a vetted Mercedes specialist — they can confirm the engine code from the vehicle's service history or on a lift.
Check the engine code against the chassis code in the index above. For example, an OM651 from a W204 C-Class will also fit a W212 E-Class or X253 GLC, but you must confirm the variant (DE22 LA vs. DE22 LA EVO) and ECU compatibility. Always consult a specialist before buying.
Based on our data, the OM654 is significantly more reliable than the OM651. The OM642 V6 is also robust, but swirl flap and oil cooler seal failures are common at higher mileage. See the OM654 Knowledge Centre for the full reliability verdict.
Theoretically yes, but practically no. The engine mounts, ECU, wiring loom, fuel system, and exhaust are all different. It is almost always cheaper and simpler to replace the engine with the same type. The fitment matrix shows factory-fit options only.
Supply-only costs vary widely. An OM651 reconditioned unit is around £2,800–£4,800 [EM-QUOTE]. An OM642 V6 diesel is £3,200–£5,500. An M276 petrol V6 is £3,800–£6,500. For a full breakdown, see replacement cost by engine code.
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 and buy a replacement. This threshold is based on our proprietary data and is a genuine guideline, not a hard rule. See the repair/replace/scrap framework for worked examples.
Every Mercedes owner considering an engine replacement or swap should start here. Wrong fitment is the most expensive mistake you can make — an engine that doesn't match the chassis won't fit, won't communicate with the ECU, and won't pass MOT. Use this index to identify your engine, confirm the chassis fitment, and then get a quote from a vetted specialist.
Once you have the engine code and chassis, the next step is understanding the cost. Use the cost guide and the repair vs. replace calculator to make a financially sound decision.
Check Your Engine with Registration LookupReady to check your engine or get a quote? Compare prices from vetted Mercedes specialists.