The 3.0-liter inline 6-cylinder Mercedes M256 engine has been assembled by the company since 2017 and installed on its most powerful and expensive models, such as the S-Class, GLS-Class or AMG GT. There is a version of the engine with one turbine and an additional electric compressor.
The R6-family includes: M103 E26, M103 E30, M104 E28, M104 E30, M104 E32, M256 E30.
Specifications
| Production years | since 2017 |
| Displacement, cc | 2999 |
| Fuel system | direct injection |
| Power output, hp | 367 (M 256 E30 DEH LA GR) 435 (M 256 E30 DEH LA G) |
| Torque output, Nm | 500 (M 256 E30 DEH LA GR) 520 (M 256 E30 DEH LA G) |
| Cylinder block | aluminum R6 |
| Block head | aluminum 24v |
| Cylinder bore, mm | 83 |
| Piston stroke, mm | 92.4 |
| Compression ratio | 10.5 |
| Features | ISG 48V |
| Hydraulic lifters | yes |
| Timing drive | chain |
| Phase regulator | Camtronic |
| Turbocharging | BorgWarner B03G (M 256 E30 DEH LA GR) BorgWarner B03G + eZV (M 256 E30 DEH LA G) |
| Recommended engine oil | 5W-30 |
| Engine oil capacity, liter | 6.5 |
| Fuel type | petrol |
| Euro standards | EURO 6 |
| Fuel consumption, L/100 km (for Mercedes-Benz GLS 450 2020) — city — highway — combined |
13.7 8.2 10.1 |
| Engine lifespan, km | ~250 000 |
The engine was installed on:
- Mercedes AMG GT X290 since 2018;
- Mercedes CLS-Class C257 since 2018;
- Mercedes GLE-Class W187 since 2018;
- Mercedes GLS-Class X167 since 2019;
- Mercedes E-Class W213 since 2018; E-Class C238 since 2018;
- Mercedes S-Class W222 in 2017 – 2020; S-Class W223 since 2020.
Disadvantages of the M256 E30 engine
- So far, no design flaws have been noted on the specialized forums.
- On other engines of the modular series, there were failures of Camtronic phase regulators.
- Like all direct injection engines, this one suffers from carbon deposits on the intake valves.
- It is also worth noting the presence of a particulate filter, uncharacteristic for gasoline engines.
