Engine Protection consist of..
1. Controlling Acid formation and wear through neutralizing of Acids.
2. Preventing Drive train wear through making oil easier to circulate, and having a thin film of slippery/protective additive and oil on the moving parts.
3.Controlling/preventing pitting by oxidizing residues.
4. Circulating and distributing Heat from hot spots in engine,thereby acting as a coolant,
5. Sealing piston ring to bore gap , and offering good sustained lubrication at all temperature.
6. Carrying blowby away ,and keeping the ingredients in suspension,and not allowing it to react with any of the engine parts.
7. The most Important function of forming a thin slippery layer ,between moving parts in a engine,ensuring least wear.




For instance, on my Hunk, the recommended grade is 10w30 and I have used Honda 10w30 mineral (excellent oil-full VFM), 10w30 HH oils (3rd class) 10w30 Veedol (another very good oil). Was planning to try the 10w40 this summer from Veedol/Shell. (mineral only)
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