Here are the 3 most reliable BMW engines of ALL TIME. First is the BMW e90/e92 M3. This engine had rod bearings that were super strong & reinforced the reliability of the engine. Second is the BMW F80 M3, F82 M4, and F87 M2 S55 engine because of its crankhub technology that acts like Honda vtec to spin super fast and give the car and antilag effect. Lastly is the BMW e60 M5 v10 because this V10 was insanely reliable, so much so that they cut off 4 cylinders and made it into the B58 engine.