Due to high taxes, Mercedes has developed a smaller displacement version of the 3-liter inline 6-cylinder engine, which in China has only 2.5 liters.
China imposes very high taxes on large-displacement engines. Manufacturers are therefore forced to offer engines tailored to the Chinese market to avoid high taxes. This is the case with Mercedes’ M256 turbocharged 3-litre inline 6-cylinder petrol engine. The Stuttgart-based manufacturer has had to reduce displacement from 3 liters to 2.5 liters to avoid high duties.
So, the engine for the Chinese market has 2,499 cc instead of 3,000 cc in Europe. The Chinese don’t publish technical data in detail, so we can’t know how Mercedes has modified this engine. But considering that it is a longer stroke engine (bore x stroke 83 x 92.4 mm) it is very likely that Mercedes kept the same bore and reduced the piston stroke to about 77 mm.
This engine can be found under the bonnet of the S-Class limousine ( S 400 L and S 450 L), the GLE (GLE 450 4Matic), and GLS (GLS 400 Matic) SUVs.
While in Europe, the 3-liter inline 6-cylinder engine in the Mercedes S 450 4Matic develops 381 PS and 500 Nm and features a 48V mild hybrid system with an integrated 23 PS starter generator, in China, the 2.5-liter inline 6-cylinder engine develops 367 PS and 500 Nm. Also available for the Chinese market is the S 400 L version with 313 PS and 450 Nm. The two models accelerate from 0 to 100 kph in 5.6 and 5.9 seconds respectively, while the top speed is limited to 250 kph.
The same engine works in the GLE and GLS SUVs. The Chinese version of the GLE 450 4Matic offers 367 PS and 500 Nm, giving it a 0-100 kph acceleration of 5.9 seconds and a top speed of 250 kph.
The Mercedes GLS 400 4Matic develops 313 PS and 450 Nm from the same 2.5-liter turbocharged inline 6-cylinder engine and accelerates from 0 to 100 kph in 6.9 seconds, with a top speed of 235 kph.
