If the engine is the heart of your car, the oil is the blood.
The oil is a lubricant that reduces friction in your cylinders. (Cylinders are like the guys in the bottom of the boat pushing and pulling the ores.) When the oil first goes into your engine, it is a translucent caramel color.
To check your on your oil color and to see if there is enough, get your Manuel to find the dipstick in your car and pull it out. Wipe it off and put it back in. (The car moving around will give you an inaccurate idea of how full the engine is.) Take it out again and that is how much oil is in the car. The dipstick should tell you where the full level is and where the lowest level can be.
As time goes by, it gets darker and thicker and does not lubricate as efficiently.
Here is some dirty oil. MMMM, tasty.
This is why we have to change the oil and the filters at regular intervals. Cars used to get oil changes every 3,000 miles, but now there are synthetic oils that can go as long as 5,000 miles. It is more expensive, but worth putting off the next oil change for at least a few months.
Those dudes at oil change shops can afford to sell such cheap oil changes because they try to tell you that all sorts of things are wrong with your car so that you will get those things done there. Usually they are wrong. Don't tell them to "suck it," or anything because it is always nice to be nice:), but check with a mechanic you trust before getting anything done.
