Hi Gurus in the house,
Please can you help throw light on how the type of engine oil we use and frequency of oil change affects fuel economy.
Nagode.

When a car engine is working, the motion of the engine parts creates friction. To overcome the resistance created by the moving parts, more fuel is consumed.

To reduce this friction, a good lubricant (engine oil) is needed. With a good lubricant, there is less resistance and less fuel is consumed in moving the engine parts.

Now the choice of oil really matters. Some oil types are very thick when cold but when put in a very hot engine, they become very thin and do not provide enough lubrication. That means you need to burn more fuel in order to overcome the resistance caused by friction of the moving engine parts.

Some oil may not really look thick when cold but they may not become thin in hot engines like some thick oil types. Note that it is not how thick an oil type is that matters, it is the way it changes with temperature that matters.

You also need to change your oil regularly because lubricants lose their power to provide proper lubrication when they are overused. When they cannot provide enough lubrication anymore, you burn more fuel.

Besides, using the wrong engine oil or overusing the engine oil in your car would make your engine lose power and wear out fast. I know you wouldn't want to do what would shorten the normal lifespan of your engine.

I hope that's clear enough.