engine oil

[Sveedy]

I'm not a physicist, so maybe " stress " is not the proper word. None the less, you can see what I mean about the different temps between say rings and walls during warm-up.
Maybe has its roots in days past with older engines and oils.

[abscate]

Back in the carb days the raw gas would wash down the oil in the cylinders and do other nasties. I’ve looked into the cold engine wear claims and just found unsubstantiated statements from the 1930 40 50 era

Think how difficult it is to measure “ engine wear on start up” and you begin to understand my skepticism

Today’s engines the FI is so much more precisely metered , the metals are better, the oils are better.

[can]

Can we say like this?
There is no connection between the engine mileage and the oil used.
You should use whatever oil recommended by the factory.

Actually, I thought differently and did some research. according to the climatic conditions of the country in which the car is used;
Up to 100000-150000 km (0w30) (0w40) (5w30) factory recommended oil should be used,
150000 km and above need to use a little thicker oil (5w40)(5w50)(10w40)(10w60) I thought

[befarrer]

The higher mileage between oil change would be for engines not in the severe duty classification. City driving would be considered severe duty. If you drove the car 100km at a time, you can get more out of engine oils. I've done oil samples on my Volvo, by 5,000km, the oil is done, not because it's worn out, but because my water content is severely high, and even the fuel content is high. Water I. Oil can cause etching, and degrage the oil. This mostly caused by short city trips and city driving, the oil is not getting hot enough. Fuel is from all of the cold starts.

[454cid]

Can we say like this?
There is no connection between the engine mileage and the oil used.
You should use whatever oil recommended by the factory.

I would agree, but unfortunately, I have not found the oil weight clearly documented by Volvo. There is a temperature range chart, and 10w30 is highlighted, but it's not expressly stated as recommended or being factory fill. I decided to go with the oil that seems to cover the widest temperatures by their chart, which is 5w40. I'm used to oil weight being explicitly stated.

[kallekula]

Don’t they just try to explain what viscosity you should use depending an outside temperature?

[abscate]

Volvo says 10W-30 specs from -20 to 40 C

That covers every user here* , which is why we welcome those long useless oil threads to move to other Fora

[MrAl]

Volvo says 10W-30 specs from -20 to 40 C

That covers every user here* , which is why we welcome those long useless oil threads to move to other Fora

Hi,

After reading your posts here i realize something maybe i havent thought about for a long time. What does 10w-30 really mean.

It's simple and im sure many people here already know this, but the "10" is an indication of the oil viscosity when the engine is cold and the "30" is for when the engine is hot. So that means the oil can flow better when the engine is cold which would be during startup.

This could be why we have heard about cold start engine wear being higher, because long time ago they probably didnt have 10w 30 just 10 or just 20 or just 30 or just 40, period. The cold start wear issue may have even been why they came up with variable viscosity engine oils in the first place. So we are already protected by using the newer types of oil with the variable viscosity.
Now maybe we could find out the relationship between temperature and viscosity of the 10w 30 oil and see how the oil responds to temperature. That would be interesting because in summer the engine is not as 'cold' as in winter. The way i understand it right now is that the 10w 30 and the like cover a wide temperature range from something below freezing to normal engine 'hot' temperature, but i think i will look around the web and see what else i can find out.

Thanks.

[454cid]

Volvo says 10W-30 specs from -20 to 40 C

That covers every user here* , which is why we welcome those long useless oil threads to move to other Fora

It does get colder than that here, sometimes (not often). Also I think it's odd that Volvo says 5w30 is only good to 68F (20C), yet 10w30 is good to 104F(40C). Somehow 30 doesn't equal 30, to them.

[can]

Volvo says 10W-30 specs from -20 to 40 C

That covers every user here* , which is why we welcome those long useless oil threads to move to other Fora

I do not think that the topics opened are useless, everyone can write their experiences.