0w20 or 5w30. what is better to pour in Forester 2020?
According to the manual, it is recommended to pour 0w20. 0w20 is written on the filler cap. pour such oil - this is what Subaru experts and engineers say. (however, in the same manual it is written that you can use 5w30, something like that). but what is it really? if you pour such oil into a car from scratch, you will definitely drive 100 thousand km under warranty, and then sell the car. what will happen next is not interesting to you. For further info, click here: best 0w-20 oil
THIS IS WHAT THE NETWORK WRITES
1. The bottom line is that SAE 0w-20 grease has quite specific characteristics and can be used only up to + 15 ° C, after this temperature it becomes too liquid for most cars, except, perhaps, Japanese cars or racing cars. These vehicles have a special motor structure, which just requires a high fluidity of the lubricant for operation due to the compression ratio and torque.
In this regard, 0w-20 engine oil is more suitable for winter use, since at low temperatures it remains fluid and does not freeze, which allows the engine to start easily even in severe frost. It will also reduce engine wear at such times.
As for most civilian cars, their engines are not as productive and demanding, so most manufacturers are starting to produce 5w-30 oil for them.
2. Comrade, be careful! This is a long technical article, not sure - don't read it !!!
0W-20 oil: adore or feared?
When automakers began to use 0W-20 oils, many people, even quite experienced in the motor business, made an indiscriminate conclusion that, they say, "the motor will not last long on this spindle."
This conclusion is due to the false stereotypes ingrained in the minds of non-specialists: “abundant lubrication is good, poor lubrication is bad”; "The thicker the oil, the thicker the oil film and the better the lubrication, which is good." And when such a person sees zero (instead of ten) in the oil marking, and 20 instead of 40, then a short circuit occurs in his head, and he immediately automatically concludes that it is too “liquid” and will not provide good lubrication.
THIS IS WHAT THE NETWORK WRITES
1. The bottom line is that SAE 0w-20 grease has quite specific characteristics and can be used only up to + 15 ° C, after this temperature it becomes too liquid for most cars, except, perhaps, Japanese cars or racing cars. These vehicles have a special motor structure, which just requires a high fluidity of the lubricant for operation due to the compression ratio and torque.
In this regard, 0w-20 engine oil is more suitable for winter use, since at low temperatures it remains fluid and does not freeze, which allows the engine to start easily even in severe frost. It will also reduce engine wear at such times.
As for most civilian cars, their engines are not as productive and demanding, so most manufacturers are starting to produce 5w-30 oil for them.
2. Comrade, be careful! This is a long technical article, not sure - don't read it !!!
0W-20 oil: adore or feared?
When automakers began to use 0W-20 oils, many people, even quite experienced in the motor business, made an indiscriminate conclusion that, they say, "the motor will not last long on this spindle."
This conclusion is due to the false stereotypes ingrained in the minds of non-specialists: “abundant lubrication is good, poor lubrication is bad”; "The thicker the oil, the thicker the oil film and the better the lubrication, which is good." And when such a person sees zero (instead of ten) in the oil marking, and 20 instead of 40, then a short circuit occurs in his head, and he immediately automatically concludes that it is too “liquid” and will not provide good lubrication.
In reality, the situation is not so straightforward.
For example, for long-term operation of piston rings, cylinders and pistons, the lubrication should not be too abundant (which will lead to increased oil consumption for waste, its severe contamination and rapid aging), but it should not be too meager (which will entail increased wear of parts of the CPG and is fraught with piston seizure).
The oil supply to the piston grooves and the thickness of the oil film in the cylinder should be as small as possible, but at the same time sufficient to ensure the requirement for good lubrication, flush the grooves and ensure the liquid friction of the rings for most of the piston stroke. In a word, as is often the case when designing equipment, the engineer needs to intuitively find the golden mean - guess the correct balance so as not to fall off the thin rope on which he constantly has to walk.
Until now, the designers have not come to an agreement on what should be the optimal oil viscosity to meet such complex and mutually contradictory requirements. And since the correct mode of lubrication largely depends on the design of the piston and rings, and given that the temperature range of oil operation when lubricating parts is very wide (from negative temperatures to 300 C), and the viscosity of the oil can vary very much (a thousand or more times) with a change in temperature, and also dozens of times increase with an increase in pressure, it becomes clear that the value of "viscosity 100 C" when assessing the efficiency of the oil in the ring-groove and ring-cylinder interfaces cannot be the only criterion for concluding that , whether the parts will be well protected from wear at such a viscosity or poorly.
For example, for long-term operation of piston rings, cylinders and pistons, the lubrication should not be too abundant (which will lead to increased oil consumption for waste, its severe contamination and rapid aging), but it should not be too meager (which will entail increased wear of parts of the CPG and is fraught with piston seizure).
The oil supply to the piston grooves and the thickness of the oil film in the cylinder should be as small as possible, but at the same time sufficient to ensure the requirement for good lubrication, flush the grooves and ensure the liquid friction of the rings for most of the piston stroke. In a word, as is often the case when designing equipment, the engineer needs to intuitively find the golden mean - guess the correct balance so as not to fall off the thin rope on which he constantly has to walk.
Until now, the designers have not come to an agreement on what should be the optimal oil viscosity to meet such complex and mutually contradictory requirements. And since the correct mode of lubrication largely depends on the design of the piston and rings, and given that the temperature range of oil operation when lubricating parts is very wide (from negative temperatures to 300 C), and the viscosity of the oil can vary very much (a thousand or more times) with a change in temperature, and also dozens of times increase with an increase in pressure, it becomes clear that the value of "viscosity 100 C" when assessing the efficiency of the oil in the ring-groove and ring-cylinder interfaces cannot be the only criterion for concluding that , whether the parts will be well protected from wear at such a viscosity or poorly.