It works as a lubricant for the engine and as a means of cooling and cleaning internal engine parts. Your engine oil is the most important fluid to check because running your engine when it is low on oil can result in serious engine damage. The best time to check your engine oil is when your vehicle has not been running for a while. If you have been driving your vehicle, waiting at least an hour will give you the best results. This will give the engine time to cool down and the oil will drain back into the oil pan.
Cool oil stays on the dipstick better, making it easier to measure the oil level.
The cooler the engine, the less risk you have of incurring an accidental burn. The vehicle's engine should not be running. Make sure the vehicle is on level ground. After opening your hood, find the engine oil dipstick and remove it. Wipe off the end of the dipstick with a rag, and notice the markings located near the end of the dipstick.