Is synthetic oil really better than regular oil?

[gautam]

HI Jimmys,

I hope this is not going to confuse you, but I must take serious issue with the answers given by @salmanahmed, and here is why.

1.)

12 hours ago, salmanahmed said:

Stick chemicals:

Each company calls them with their own brand name. But if you have seen the caltex petrol ad, they add a chemical to their petrol which is called "techron". This chemical cleans the engine by removing the carbon deposit. Similarly, there are chemicals which reduces the affinity of oil and internal engine and helps it stick to the internal walls of the engine body as well as reduces the ability of particular to stick to the internal walls of the engine. You can see the tech sheet of any renound brand and you will find the information there.

First off, "Techron" does what @salmanahmed says it does, but that has nothing to do with how long oil lasts, or how well it lubricates an engine.

Secondly, there are no chemicals or additives in oil that makes the oil "stick" to the internal engine parts. Over the past decade or so, car makers have developed new metals and metal coatings that have a natural affinity for especially synthetic oil molecules. What this means is that the metal "attracts" oil molecules, which is entirely a reaction between the metal and the oil, which prevents dry start ups because all metal surfaces are permenently coated with a layer of oil.

2.)

12 hours ago, salmanahmed said:

Factors affecting oil's age:

Oil loses its ability to lubricate as it is consistently exposed to extremely temperatures. This causes oil to lose its color and texture and stickiness. These are the things which a mechanic tries to judge by putting a drop of oil between the tips of his finger and feel the oil texture, and lubrication. 

While heat does play a role in how long oil lasts, it is in fact the combination of heat and contact with moisture and oxygen that causes the additives in the oil to break down. The oil itself does not break down, but oil without additives has very limited  lubricating properties, and therefore even synthetic oil needs additives to work.

When the combustion products in oil come into contact with moisture from the atmosphere, sulphuric acid forms, and while some additives prevent this from happening when oil is new, at some point the acid build-up exceeds the additives' ability to prevent it. Sulphuric acid breaks down the additives that makes the oil flow, which is why oil that has a lot of acid in it gets thick, and sometimes so thick that it can no longer be pumped to all parts of the engine, which results in extreme mechanical wear. By the way, oil only turns black because it mixes with the carbon and other products of the combustion process. Age by itself does nothing to change oil's colour. 

Contact with atmosheric oxygen on the other hand, breaks down the friction modifying additives (mostly zinc), which means that after a while, the additive can no longer form a protective barrier between matal surfaces. Note that the oil itself does NOT provide this barrrier- all the oil does is carry the zinc to where it is needed. The zinc is in the form of little "plates" that slide over each other between contact surfaces, so if the zinc breaks down, there is nothing to prevent direct metal to metal contact.

The reason why syntetic oil last longer than regular oil is the fcat that all the molecules are the same size on the one hand, and that the molecules are "tougher" and more difficult to break down than those in regular oil, on the other. Synthetic oil also does not contain all the different waxes, gums, and varnishes in regular oil that takes up volume, but contributes nothing to the lubrication of the engine. 

Even so, while synthetic oil lubricates better than regular oil, it needs exactly the same additives that are in regular oil (but not quite in the same amounts), since it is better at withstanding the combined effects of heat, and contact with moisture and oxygen.

I hope this clears up some of your questions and doubts, but as @salmanahmed says, feel free to ask anything else if something is not clear.    

[salmanahmed]

i don't really like to copy and paste stuff, but sometimes there is no simpler way:

"Briefly, there are two types of "synthetic" oils on the market. Group IV oils consist of molecules that are synthesized from simpler chemical compounds. This lets the chemical engineers "tune" the characteristics of a lubricant to exact specifications. These oils flow more freely at extreme low temperatures and don't break down at very high temperatures. As a side benefit, they generally can be specified one or two grades lighter than a mineral oil, which consumes less energy as friction inside the engine and saves fuel."

For more please read here: http://www.popularmechanics.com/cars/how-to/a2316/4232672/

If you still want to read more then go through this PDF:

Oils produced by synthesis (chemical reaction) rather than by extraction or refinement. Many (but not all) synthetic oils offer immense advantages in terms of high temperature stability and low temperature fluidity, but are more costly than mineral oils. Major advantage of all synthetic oils is their chemical uniformity. 70% of synthetics contain Polyalphaolefin.

[note: Polyalphaolefin is a chemical  ]

Synthetic Oil is entirely produced by a chemical process. Like H20 is a chemical compound, normally know as water and NaCl is a chemical compound commonly know as Table Salt or simply salt. We have a chemical compound which we call Synthetic Oil. Produced and fine Tuned by Chemical Engineers. 

For more read this link's content: http://www.rsareliability.com/Report on Synthetic Oil.pdf

The comments that i leave here are not for winning an argument (take it or leave it), you could have more knowledge than me on a subject or vice versa. I come here to learn and not to fight. Hope that the above mentioned helps answer a few questions and concerns. 

Peace out buddy. 

[gautam]

Hi salmanahmed,

Thanks for the info, but I don't have any more questions or concerns. Your post  just confirmed everything I have been saying, so thanks again!