The Role of Lubricants in Diesel Engines Why Engine Oil Is More Than Just a Fluid In the commercial trucking industry, diesel engines are the workhorses that drive everything from urban delivery vans to long-haul 10-ton trucks. To keep these engines running smoothly, one element is absolutely essential: lubricant oil. Far beyond just “oil,” engine lubricants are critical for performance, durability, and reliability—especially in used Japanese trucks operating in demanding environments.
