The BMW M57 engine is a 3.0-liter inline-six turbo-diesel engine introduced in 1998, famous for its power, durability, and smooth torque delivery . Featuring a cast-iron block, aluminum cylinder head, and common-rail fuel injection , it combines performance with long-term reliability. Found in BMW sedans, SUVs, and performance models, the M57 is highly regarded by enthusiasts for its tuning potential, off-road adaptability, and engineering excellence , making it one of BMW's most iconic diesel engines.