Ask a mechanic what happens when your vehicle runs out of engine oil, and you're likely to get a simple answer: game over. That's it for your engine. Knowing about the effects of low oil on an engine will help drivers avoid carelessness that is likely to result in a grounded vehicle.
When an engine runs low on oil, it lacks the lubrication necessary for helping the metal parts move quickly against each other. When the shortage of engine oil reaches a critical mass point, the parts of the engine start to grind. The vehicle is likely to come to a screaming, clattering, shuddering stop. Fixing the engine will be a big job, and usually, these engines will simply be replaced, as they have been practically ruined.
Drivers can avoid this terrible situation simply by periodically checking the engine oil indicator or "dipstick." This small metal piece is generally labeled and referred to in the owner's manual for the vehicle. The driver just opens the hood, pulls out the dipstick, and wipes it off before re-inserting it into the oil pan. Then he or she removes it again and reads it to make sure the engine oil level falls in the desired range indicated.
This process of checking engine oil is much more important for older vehicle that may lose oil faster through leaks or burning oil situations. Check your oil often to make sure you don't run dry.