When you buy a wheel loader, you will first consider the loader's engine, because the engine is the core component of a loader, but the role of engine oil cannot be underestimated. Engine oil mainly lubricates the surfaces of various parts inside the engine. It can reduce the friction and wear of parts, and also has the functions of cooling, cleaning, sealing, rust prevention, buffering, etc. The following are the steps on how to correctly check the engine oil level.