What are the main differences between synthetic and dino oil?

Is one always better than the other?

  • 2
    We need to be careful not to invite a religious debate here. C# vs. Java? Mac vs. Windows? Etc. This is also far from the type of question an expert might ask.
    – Jay Bazuzi
    Mar 12, 2011 at 3:32
  • 2
    I am shocked to see people responding like the commenter above. This isn't like Christianity vs. Islam, this is like Creationism vs. Evolution. There is no evidence, nor even a well reasoned argument, to support the claim that organic oil is ever better than synthetic oil in a modern combustion engine.
    – Kyle Baker
    Dec 4, 2016 at 1:22

5 Answers 5


A full synthetic oil, as the name states, is "synthesized". By that, they mean it is made in a lab, it is a manufactured product.

Organic (Dino) oil is a product of nature.

So the big difference is the environment in which the oil is made in.

The main selling point on synthetic over organic is because it is manufactured, it is made in a controlled environment. That means far less impurities and a more consistent product.

Organic oil will be influenced by what it was made from, what was in the ground where it was extracted from, etc.

Another way to think about it is synthetic is an additive process. They start with nothing and add in the components they want until they get the end product.

Organic oil is a reductive process, they start with an unrefined product and filter out all the stuff they don't want until they have what they want left.

  • 5
    That is a big huge debate full of myths, half truths, obscure references, etc. All things being even, most people will agree synthetic because of the less impurities and consistent product. But there are a whole lot of disagreements on if it is ok in older vehicles, vehicles that have lived their lives on organic. Then you'll get into whose brand is better as they all use different formulas and additives.
    – ManiacZX
    Mar 11, 2011 at 6:19
  • 1
    I'll say it again: There is no evidence, nor even a well reasoned argument, to support the claim that organic oil is ever better than synthetic oil in a modern combustion engine. The only net effective difference is level of impurities in the oil--oil from a lab doesn't have those impurities. End of discussion. Everything else is heresay and anecdote.
    – Kyle Baker
    Dec 4, 2016 at 1:23

Wikipedia has a great page on Synthetic Oils, specifically their performance.


  • Better high and low temperature performance. They act more like a thinner oil at lower temperatures and like a thicker oil at higher temperatures, without the disadvantages of multiviscosity oils like 10W40. Especially useful when initially starting.
  • Reduced problems with sludge, breaking-down, particularly in very high temperatures like in the turbo.
  • Better lubrication properties.
  • Extended change intervals.


  • Higher cost.
  • Too slippery for properly seating parts during initial break-in.

It's not a case of one being unconditionally better than the other, for automobile applications. For example:

  • Rotary engines such as in the Mazda RX series of vehicles should not run synthetic oil.
  • Some vehicles come from the factory with synthetic oils, recommend using traditional "dino oil" for the initial break-in.
  • There is debate about whether using synthetic oil in a car that has run regular oil for a long time is a good thing. The theory is that synthetic oils can clean out sludge and varnish that has built up. This sludge can dry up seals, and then when cleaned out leaks can develop in an engine that otherwise would have been tight.
  • While synthetic oils are better in many regards, it may be that the average automotive applications aren't demanding enough to take advantage of them.
  • 1
    There are errors in this answer. (1) "Too slipperty for properly seating parts during initial break-in". That is an old wives' tale. It's not in the wikipedia article, and it's not anywhere that has a reputable source. (2) Any car engine will benefit from having fewer impurities in its oil--if you disagree, go melt a candle in your oil before you put it in your car.(see: bit.ly/2gUaCyo) (3) Mazda's own racing team has used synthetic oil in their cars, and as far as I can tell, they seem to not recommend synthetic oil only because they haven't sufficiently tested it.
    – Kyle Baker
    Dec 4, 2016 at 1:19

Oil still gets dirty. Syn might not break down as fast as dino and have better cold start properties etc, But engines still wear and there is still by-product of combustion that gets transferred to the oil. I would suggest changing the oil filter at 3000-3500 miles on a 7000 mile oil change with syn. On this annual change syn,same filter change interval ,3000-3500 miles. Sludge doesn't appear to be a problem with syn and it appears to offer better protection. But it's nice to have a choice.


I restored a 66 Chevelle SS with a 502 crate motor. Ran synthetic for two years burning a quart every 800 miles. Oil was black when I changed it. Ran dino for 6,000 miles at the advice of a mechanic. Oil after second change was amber and no burn. Went back to synthetic and no oil burn. Just my experience and don't mean to create a fight here. Just my experience.


Although many people do not drive there cars hard enough to need synthetic oils, being able to go 10k miles before a change makes them cheaper in the long run, though more expensive per oil change. And when living in an area where temperatures get below -20, it can really help with starting. Also if you care about the environment, they are better for it too.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .