what is the difference between motor oils?

Answer 1

As long as you use the weight and grade motor oil recommended by the manufaturer of the car, there is no real difference among brands.

Consumer Reports tested motor oils by putting them in New York City taxis and checking the tolerances on wear surfaces before and after running them hard for many miles. There was no measurable difference in protection among all the oils tested.

This was not the most severe test, however, because the cars ran continuously, so there were no 'cold starts,' the toughest test your oil must face.

Full synthetic oil, like Mobil One or Castrol Syntec protect better in this case. Because they have a wider viscosity index (thicken less with cold, thin less with heat) they are thinner after sitting while you work or sleep, so that the oil pump can get it to where it is needed to protect against wear quicker.

Synthetics also thin out less as your engine heats up, so they maintain the protective film better and under more severe conditions.

Finally, a synthetic oil's light fractions (thinner components) are less volatile, so they don't evaporate as readily, making the oil more stable and longer lasting.

Answer 2

Marketing

Answer 3

all motor oils must meet standards, after that it'll be the additives that are in each one..., how each is made, whether or not it's organic or synthetic...

Answer 4

WELL TO TELL YOU THE TRUTH THEY ARE BASICLY THE SAME ASEPT THAT ONE IS THICKER THEN OTHERS AND ONE MIGHT BE CLEANNER THEN THE OTHER AND MIGHT BE A BETTER BRAND AND THATS ABOUT IT OK

Answer 5

http://en.wikipedia.org/wiki/Motor_oil