Scotty Kilmer is rather renowned in the automotive world — and if you’ve never heard of him, you should definitely look him up. As most icons are, Scotty Kilmer is rather opinionated, and because of his extensive background in the field, well, we really can’t blame him. When it comes to car myths, he isn’t shy to call people out, so his latest video, “7 Engine Oil Myths Stupid People Fall For,” might have you second-guessing whether you have all of your facts about engine oil maintenance straight.

Why is engine oil important?

Engine oil is an essential component of all combustion engines regardless of type, size, or style. Vehicle engines are made up of many moving parts, most of them being metal, which rub against one another or are exposed to harsh conditions like the internal combustion process. Engine oil works as a lubricant to reduce the effects of friction on these internal parts and helps to absorb the heat produced by that friction.

But, motor oil isn’t perfect, and while the market has grown to produce different types of oil, like synthetic, there is no way to stop it from degrading with time and use. This is why having the correct amount of oil, but also getting your oil changed out at regular intervals, is so important.

Some surprising oil facts that are actually untrue

I’ve always believed that when a vehicle’s motor oil turns black, that means it’s time for a change. After all, that’s how most of us are taught to gauge how much life oil has when we pull out the dipstick. Scotty points out that the engine oil turns black as a result of oxidation, which occurs naturally over time and becomes more pronounced with higher engine temperatures. Color isn’t the only factor that you should keep in mind when looking at your engine oil, but rather how dirty the oil actually is — like if it’s gritty or has a lot of particulates.

Using thicker oil to protect your engine

The confusing numbers on the front of the oil containers explain a lot about each specific oil’s viscosity. Each car’s engine may be rated for different oil variations, with differing viscosities based on several factors such as engine type and performance level. While using thicker engine oil than recommended is sometimes a habit with older cars that have worn down mechanical parts, this isn’t a good habit for newer engines. In fact, using thicker engine oil than necessary can lower the engine’s overall efficiency.

There are still more myths included in Scotty Kilmer’s videos, but they aren’t as commonly known. But, you may be surprised to hear some of them as myths you personally believe. Luckily for us, there is a scientific explanation to debunk all of these pesky engine oil myths so we can continue to maintain our engines in the best way possible.