Big-Foot said:
1) Oil (fossil or synthetic) never wears out - it only becomes contaminated or diluted. No exceptions.
Does this include petroleum breaking down, such as it working under heavy load or hot conditions that will effect petroleum before synthetic?
Big-Foot said:
2) Neither Fossil or Synthetic oils are resistant to contamination or dilution. No exceptions.
Agreed, the quality of the base stock and additive package play an important part in just how resistant the oil is.
Big-Foot said:
3) Running extended drain intervals of synthetic oils will mean the continued circulation of impurities through your engine. No exceptions.
Also true, and again the oil additive package plays an important part in neutralizing these impurities as well as filtration in being able to remove them. Recently a rep for GM was commenting on running oils for high extended drains and that it is possible if oils were formulated properly. Most companies today are not looking to formulate an oil to last as long as they are actually capable of going, they would rather have the profits from a more frequent change. In Europe oil specs are more strict and are rated for longer drains. Amsoil is not the only one promoting extended drains, Mobil 1 last year released their Extended Performance oil with a recommended drain of 15K, so the science is there, it just depends on whether the manufacturer wants to market it.
Big-Foot said:
4) Use of a good quality oil filter is of paramount importance in removing "some" impurities from your engine as the system accumulates them. He has yet to find a filter that would remove all impurities or reduce the dilution of any oil.
Very true, and no filter can capture all of them, but the more the better. This is also why some people, particularly diesel owners, tend to add a bypass filter to capture as much as possible. While technology will change so we can build a better filter, I doubt we will ever have something that will take care of everything.
Big-Foot said:
What is synthetic oil?
Synthetic oil is an assembly of synthetically blended hydrocarbons that duplicate those in fossil based oil. The only difference between Synthetics and Fossil is that Fossil based oils have impurities and inert ingredients in them from the start - whereas the synthetic based lubricants have very few. It is the lack of impurities in the synthetic oils that make them more "slippery" than their fossil based counterparts. Less friction = more HP and less wear.
One of the best comparisons I have heard was to think of petroleum as a bowl of fruit of various sizes and shapes: grapefruit, apples, oranges, grapes, etc. The more impure the oil, the more sizes of "fruit." Some boil off when it gets to hot, causing the oil to thicken, and even cause friction when rubbing against each other. Synthetic would be a bowl of golf balls. All the molecules are the same size, absorbing the same amount of heat and rolling evenly against each other and the surfaces. These cause less friction and cause temps to drop and the oil to be more stable, which can help to produce more HP and better MPG.
Group III Synthetics are actually petroleum based synthetics. Most of the more common synthetics on the market today fall within this group. Consider this a more uniform bowl of fruit. It still will be apples, oranges, etc., but they will be more uniform rather than with the large variations that a Group II standard petroleum will have. There are even different grades of Group III base stocks depending on what quality the manufaturer wants their oil to be. Group IV (PAOs) and Group V oils (usually Esters) are what most die-hards consider the "pure synthetics" which will be the most uniform and pure.