QUOTE (Tourist @ Apr 14 2013, 12:40 AM) <{POST_SNAPBACK}>
Like you, I have done some research on this issue and your own research clearly shows that Mineral Base Oil has absolutely no problem when we are talking about merely 10,000-km OCI. There are other engine manufacturers saying the same thing as Mack aka, Synthetic Oil does not extend OCI because it's the additives & soot that determine OCI. As for Scania, their OCI can go up to 120,000 km using 15W40 (and 15W40 is most likely to be Mineral).
It's the engine manufacturers who decide which API or ACEA or JASO grade and viscosity should be used. And if none are available, manufacturer can set their own specific requirement and it's up to oil company to produce. So it's not entirely true engine manufacturers has no control over engine oil quality. They dictate quality.
One small point. OCI are dictated by soot and additives. Mineral Base Oil probably handle soot better than Synthetic Base Oil. And soot is a huge problem with diesel engine especially with EGR equipped engine, less so for gasoline engine. So Mineral Oil probably is a better choice over Synthetic and at a far cheaper price. When we talk about 10,000-km, you probably are not going to see any advantage of Synthetic over Mineral whatsoever. So from an economic point of view, it's unwise to pick Synthetic.
And I absolutely agree about your last point. A Synthetic Oil from a no-name brand may even be worst than a Mineral from a reputable brand and reason why we only stick to Delo-400 15W40 for our diesel trucks. It's one of the best out there and when compared to Synthetic, dirt cheap. And we NEVER have any engine oil related problem, even up to 500,000-km when truck sold off. So we see absolutely no need for Synthetic.
So we can safely conclude the often found statement "Mineral last 5000-km and Synthetic last 10,000-km" to be nonsense and without any scientific basis.
It's the engine manufacturers who decide which API or ACEA or JASO grade and viscosity should be used. And if none are available, manufacturer can set their own specific requirement and it's up to oil company to produce. So it's not entirely true engine manufacturers has no control over engine oil quality. They dictate quality.
One small point. OCI are dictated by soot and additives. Mineral Base Oil probably handle soot better than Synthetic Base Oil. And soot is a huge problem with diesel engine especially with EGR equipped engine, less so for gasoline engine. So Mineral Oil probably is a better choice over Synthetic and at a far cheaper price. When we talk about 10,000-km, you probably are not going to see any advantage of Synthetic over Mineral whatsoever. So from an economic point of view, it's unwise to pick Synthetic.
And I absolutely agree about your last point. A Synthetic Oil from a no-name brand may even be worst than a Mineral from a reputable brand and reason why we only stick to Delo-400 15W40 for our diesel trucks. It's one of the best out there and when compared to Synthetic, dirt cheap. And we NEVER have any engine oil related problem, even up to 500,000-km when truck sold off. So we see absolutely no need for Synthetic.
So we can safely conclude the often found statement "Mineral last 5000-km and Synthetic last 10,000-km" to be nonsense and without any scientific basis.
Just to share,
ExxonMobil Research and Engineering had reported that;
" High isoparaffinic base stocks, however, are advantageous in soot control for diesel engine lubricants. Lower soot-induced viscosity increase and lower soot-induced wear are observed for diesel engine lubricants with higher saturate contents."
*High isoparaffinic base stock is in layman term known as synthetic base oil. According to API, the synthetic base oil must consists of more than 90% saturates.
I respect your view of economical way of maintenance for engine, where many vehicle owners who have budget constraints would be benefited from your advice, but saying synthetic oil is just waste of money because it offers no advantage at all is also not correct...
