Why Do German Cars Burn Oil While Japanese Cars Don't?

[Minnie]

German cars' cylinder wall design plays a crucial role. Due to more oil adsorption on the cylinder walls, a slight amount of oil on the combustion side evaporates more and is carried away during combustion, resulting in higher oil consumption compared to ordinary honed straight-grain structures. This is especially noticeable at low engine speeds. More details are as follows: 1. Cylinder Wall Design: Japanese cars differ from German cars in this aspect. Most Japanese cars have smooth cylinder walls with tight sealing, ensuring good cylinder pressure and allowing the engine to generate high torque even at low speeds. Compared to cross-hatched cylinder walls, smooth walls don't retain as much oil, leading to lower oil consumption. 2. Piston Ring-to-Cylinder Clearance: Another reason is that German cars typically have larger piston ring-to-cylinder clearances compared to Japanese cars. Japanese cars maintain better sealing between pistons and cylinder walls. Overall, the main reasons German cars burn more oil than Japanese cars are differences in cylinder wall design and piston ring-to-cylinder clearances.