What makes an engine require synthetic oil?

The cheapest synthetic oil is better than any fossil oil.
So you feel that the cheapest "synthetic" from a blender which buys both the base stock and add pack from somewhere.

Vs something like a Havoline "blend" who make both the base stock and add pack themselves and put there brand name on it?

I am not saying your wrong, but do you have any data for this?

I think thats why so many VOA are posted. Its not really that simple.
 
So you feel that the cheapest "synthetic" from a blender which buys both the base stock and add pack from somewhere.

Vs something like a Havoline "blend" who make both the base stock and add pack themselves and put there brand name on it?

I am not saying your wrong, but do you have any data for this?

I think thats why so many VOA are posted. Its not really that simple.
What does the VOA show in this regard?
 
It it for longer oci? Specific type of timing chain? Any other things?


Our 2013 can am calls for a synthetic 5w40 year round. Imo I'd rather use a 10w-40 in it or maybe a 10w-30. Why can't I use a non synthetic in it?
An engine doesn't "need" synthetic.

Every oil question is always a question of sufficiency. What oil is *sufficient*? And what is the measure of it? Sufficiently clean? Sufficient in wear protection? Sufficient in cold flow?

I use the premium oils because I know they will always be "sufficient."

But would regular Maxlife or even cheap Valvoline Daily Protection be sufficient to keep my 20 year old van running until next summer? Of course they would. Heck, almost any group II based oil would keep my van happy the rest of its life, because it's near the end of its life. Whatever value there is to be had from premium oils I've already accrued, and using premium oils is probably a waste of money.

But I do it anyway, because it's necessary for my self-respect.
 
It it for longer oci? Specific type of timing chain? Any other things?


Our 2013 can am calls for a synthetic 5w40 year round. Imo I'd rather use a 10w-40 in it or maybe a 10w-30. Why can't I use a non synthetic in it?
Dubber09 gave you a good concise answer.
Now you will not find a 5W-40 in regular oil.
Mineral Oil has made great strides in the last decade so you don't HAVE to use synthetic s long as you understand
the differences.
Mineral Oil is made-up of 3 types of molecule, small-medium-large. The 1st & last get burned out and end up as deposits on the valves & piston, the medium provides lubrication.
Synthetic Oil is made-up of only medium-size molecules so no deposits.
Synthetic of same weight will protect up to 10c higher temperature and provide much faster flow in sub-zero temperature.
As I keep my vehicles a long time I do not go for extended OCIs or Oil analysis, for the amount of oil in my vehicles there is hardly any financial benefit (Different story if your Oil Capacity is in Gallons vs Liters)
Not to get too involved this ought to be enough for you to make a decision.
 
I’m not convinced that an engine requires synthetic oil, but certain grades such as 0W40, 5W50 and the like do.
Conventional grades such as 10W40 and 5W30 typically have high treat levels of viscosity modifiers which may shear down before the recommended drain interval.
 
Dubber09 gave you a good concise answer.
Now you will not find a 5W-40 in regular oil.
Mineral Oil has made great strides in the last decade so you don't HAVE to use synthetic s long as you understand
the differences.
Mineral Oil is made-up of 3 types of molecule, small-medium-large. The 1st & last get burned out and end up as deposits on the valves & piston, the medium provides lubrication.
Synthetic Oil is made-up of only medium-size molecules so no deposits.
Synthetic of same weight will protect up to 10c higher temperature and provide much faster flow in sub-zero temperature.
As I keep my vehicles a long time I do not go for extended OCIs or Oil analysis, for the amount of oil in my vehicles there is hardly any financial benefit (Different story if your Oil Capacity is in Gallons vs Liters)
Not to get too involved this ought to be enough for you to make a decision.
Are you sure about all of that? I never knew the details of all that chemistry.
 
It it for longer oci? Specific type of timing chain? Any other things?


Our 2013 can am calls for a synthetic 5w40 year round. Imo I'd rather use a 10w-40 in it or maybe a 10w-30. Why can't I use a non synthetic in it?
I would be willing to bet that the manufacturer is "recommending" not requiring their expensive branded syn oil. Most manufacturers recommend synthetic because their is no reason not to, besides a little cost. Synthetic is better in every way, so why not recommend the best. An engine manufacturer cannot legally mandate the use of a specific brand or type of motor oil, including synthetic, under the Magnuson-Moss Warranty Act.
 
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I would be willing to bet that the manufacturer is "recommending" their expensive branded syn oil...
Why would they ? They are not the ones selling the oil - the dealer is. A dealership can charge any amount of zeroes behind the first digit, as long as they get the customer to bite - which they do. They can sell frozen yogurt in these barrels, they'll still decide the markup.

I think whenever a manufacturer releases oils and fluids under their brand, it's when a new standard or type comes out, and they want to make sure there's at least one product that fits and works. And when it's exotic enough - that there's at least one product that is available for the dealer to order.

For "simple" oils there's usually a sticker of whatever the manufacturer/importer currently recommends. My Hyundais used to come with Shell recommended, then with Quaker.
 
Why would they ? They are not the ones selling the oil - the dealer is. A dealership can charge any amount of zeroes behind the first digit, as long as they get the customer to bite - which they do. They can sell frozen yogurt in these barrels, they'll still decide the markup.

I think whenever a manufacturer releases oils and fluids under their brand, it's when a new standard or type comes out, and they want to make sure there's at least one product that fits and works. And when it's exotic enough - that there's at least one product that is available for the dealer to order.

For "simple" oils there's usually a sticker of whatever the manufacturer/importer currently recommends. My Hyundais used to come with Shell recommended, then with Quaker.
If a dealer is selling a manufacturer branded oil I can guarantee the manufacturer is getting a cut of anything with their name on it. If a manufacturer is recommending a brand it's a paid recommendation, not requirement.
 
I don't overthink this. When it's time for an oil change, I go to Walmart and buy a 5-quart jug of Mobil 1 full synthetic along with an M1 oil filter. Total cost is under $40. Problem solved. Seems that every time I go into the store there's less syn blend and less "regular" motor oil on the shelves.
 
If a dealer is selling a manufacturer branded oil I can guarantee the manufacturer is getting a cut of anything with their name on it. If a manufacturer is recommending a brand it's a paid recommendation, not requirement.
But of course. Not claiming the opposite. Just saying that I doubt they rake so much money off it that they'd try to push it. Brands are smart enough not to do it. When Hydrospace (aka HSR aka HSR-Benelli aka Belassi) started in the US, they had some statements on what specific oil should be mandatorily used. They quickly recanted.
 
It grinds my gears that I see the engine barely ever going to temp, with all the ons and offs on short trips.
That would only be impacted by the 0, not by the 20 wouldn't it.

Regardless, 0W-20, 0W30 and 0W-40 oils don't have the same viscosity at any temperature. However the lower viscosity oil will always get quicker to operating temp. and lubricates better even prior to that.
 
Regardless, 0W-20, 0W30 and 0W-40 oils don't have the same viscosity at any temperature. However the lower viscosity oil will always get quicker to operating temp. and lubricates better even prior to that.
A higher viscosity oil heats faster. Engine RPM is the main driver through shear heating in the bearings.
 
I wouldn't even think of doing that.
Agree. I see weekly what long oci do to engines. And no I don't need 500 people saying "I have run 10k intervals with no problems. ". Bottom line is this oil is cheap, & dirty oil circulating is not as good as cleaner oil. For under $50 I'll change every 5k as will most auto techs. Cheaper than a tank of gas these days.
 
Agree. I see weekly what long oci do to engines. And no I don't need 500 people saying "I have run 10k intervals with no problems. ". Bottom line is this oil is cheap, & dirty oil circulating is not as good as cleaner oil. For under $50 I'll change every 5k as will most auto techs. Cheaper than a tank of gas these days.
Yet, we have people on this site having issues at 5k intervals, too. Not all oil is made equally and not all engines respond well to just any oil despite shorter intervals. Dirty oil? Well, define that. Because mileage alone doesn’t = dirty oil to the degree it’s a problem

At what point is it “dirty oil” to the point it requires changing by an arbitrary mileage? Some more reputable members here highlight that too frequent changing could even introduce more deposits due to lighter portions of the formulation flashing off early on in the OCI; if I understood it correctly. I think the correlation = causation thing isn’t a black and white idea of “just change oil more frequently” as it can be far more nuanced and depends on factors such as oil selection and the conditions a given engine is run during the interval.

Others may feel free to critique what I’m trying to get at. Mechanics obviously are going to err on the side of caution because you folks see the cars that are abused or neglected and have “just rolled in” cases show up asking what’s wrong…well, clearly not servicing the vehicle at all would be a problem! Interval alone isn’t the issue though. Neglected vehicles? Yes. Subpar oil selection? Also, can be yes.

We’re seeing some evidence of this truth with the VRP experiences of cleaning up engines that were seemingly spotless, but had piston ring deposits to some degree. As has been said, most oils provide similar levels of wear protection these days. It’s really becoming more apparent not all offer similar levels of clean running capabilities; which is more to the issue of oil selection being as more important as appropriate OCI lengths.
 
Cheaper than a tank of gas these days.

Oil in fact is being always cheaper in the US than anywhere else in the world.
This proves that whatever price a certain product has, people will always look for cheaper alternatives.

Not only that, but certain people want to run cheaper oil at 10K OCI.
 
Agree. I see weekly what long oci do to engines. And no I don't need 500 people saying "I have run 10k intervals with no problems. ". Bottom line is this oil is cheap, & dirty oil circulating is not as good as cleaner oil. For under $50 I'll change every 5k as will most auto techs. Cheaper than a tank of gas these days.
Amsoil and HPL and M1 ESP at 10k intervals are still going to be better for your engine than Kirkland/Supertech at 5k intervals….
 
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