Oil Extractor Opinion

[Dynomite]

Originally Posted by xlr8nflorida

An oil change basically breaks down like this:

12 quarts = 9 clean 3 dirty or 75% clean oil 25% dirty oil
If you added 3, 6, 9 quarts it would decrease the amount of dirty oil.
It really does not make sense to just add 3 or 6 etc as the math works out the same. If you add 9 and drop it, you are then down to 3/4 quart of dirty oil. If you refilled it again you would be alittle over 1/3 of a quart of dirty oil. Overkill for most but I don't like running around with 25% dirty oil even if its not really that dirty. It's like taking a shower and not changing your underwear.

I concur If you add 9 quarts of clean oil and drain 9 quarts of mixed oil, you end up with 3/4 quart of the original dirty oil remaining.

But....doing it your way by adding 3 quarts of clean oil and draining the mixed dirty oil leaves 1.5 quarts of the original dirty oil the first time and leaves 3/4 quarts of the original dirty oil the second time.

You got the same result with just 6 quarts of clean oil vice using 9 quarts of clean oil all at once

Your method saved 3 quarts of clean oil