The metal parts of your engine suffer the effects of friction as they rub together. This generates heat and leads to premature wear. It's a bit like water-skiing. The buoyancy of the water helps you to glide across the waves more easily.
How to Choose the Right Lubricant?
You're about to change your oil, and you're wondering which of the lubricants available on the market you should choose. It's really a choice that depends on your vehicle.