You always hear people saying to follow the manual that comes with the car. In most cases (if not all) this is the best practice. Oil changes and routine checks of other fluids or replacing oil/air filters is very effective preventative maintenance. Running your car on oil past it time to be changed can cause many issues. Many people wait till they get a check engine light and a lot of time that is a sign it too late. I recently got a check engine light on my car (even with good maintenance) and it turned out to be a broken timing chain in the engine which made one of the cylinder heads crash into a valve. This caused metal shavings in the oil pickup. What that means is I need a rebuilt engine at the tune of $10k. Makes a few hundred for routine maintenance seem very reasonable.

This strongly depends on the car, and to a lesser degree how it is used.

For a number of engines, (usually high performance, but some others) the timing ch ... Read more »