Why do we need to changes our oil base on range and time? Does the oil rot and if not why is there a date to change it?
Bonus question: is synthetic oil have an espiration date?
In: 5
Oil gets dirty and dirty oil and more specifically the debris in dirty oil can damage your engine. Synthetic oil isn’t somehow immune to getting dirty so it also goes bad.
Oil gets dirty and dirty oil and more specifically the debris in dirty oil can damage your engine. Synthetic oil isn’t somehow immune to getting dirty so it also goes bad.
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Oil gets dirty and dirty oil and more specifically the debris in dirty oil can damage your engine. Synthetic oil isn’t somehow immune to getting dirty so it also goes bad.
I think it’s the additive package that deteriorates more than the base oil. There’s things in the oil that keep it stable and keep it balanced as it’s supposed to be. Moisture, acids, dissimilar metals, etc make it harder for the oil to protect as it needs to as it gets older. As far as the synthetic base oils, I have seen some conventional oils out perform synthetic because of the stable and robust additive package. The only way to tell if your oil is still good is to have a sample sent to a lab for oil analysis.
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I think it’s the additive package that deteriorates more than the base oil. There’s things in the oil that keep it stable and keep it balanced as it’s supposed to be. Moisture, acids, dissimilar metals, etc make it harder for the oil to protect as it needs to as it gets older. As far as the synthetic base oils, I have seen some conventional oils out perform synthetic because of the stable and robust additive package. The only way to tell if your oil is still good is to have a sample sent to a lab for oil analysis.
I think it’s the additive package that deteriorates more than the base oil. There’s things in the oil that keep it stable and keep it balanced as it’s supposed to be. Moisture, acids, dissimilar metals, etc make it harder for the oil to protect as it needs to as it gets older. As far as the synthetic base oils, I have seen some conventional oils out perform synthetic because of the stable and robust additive package. The only way to tell if your oil is still good is to have a sample sent to a lab for oil analysis.
So… oil gets hot and is subject to carbon. The more you run it the darker it gets, at some point it’s so full of carbon that it becomes sticky and unable to flow into the spots it needs to lubricate.
Car oil is designed to use this deterioration in favor of the car, by making a black slime that traps any metal debris, this slime falls on the bottom of the oil tank where it confines any metal debris until an oil change removes it and the debris.
By changing the oil at correct intervals, you make sure to remove all the slime and debris and replenish the engine with oil that can repeat the process while being thin enough to go in small gaps and lubricate those contact areas.
For this reason you need to use an oil that is specific for your climate temperatures and engine type. You want the carbon to form in a controlled manner, and the oil to be thick enough to make a hard lubricant film on the moving parts, and thin enough to get into those parts.
Synthetic oil is a slightly more expensive oil that does all of the above better, in wider temperature ranges, and for longer, compared to mineral oil.
Synthetic oil is mineral oil that was chemically modified to improve the behavior.
Synthetic oil doesn’t rot or expire, same for mineral oil. The lifetime of the oil is dictated by how many hours it has been exposed to the engine operating temperatures.
Note: the biggest difference in duration is that mineral does make more carbon, lasts less, and even when is new, it doesn’t like to flow cold and doesn’t resist to high temperatures. Synthetic oil when brand new can flow perfectly at a wide range of temperatures. But when it is used past its deadline of engine time, it loses this property and becomes unable to adapt to temperatures, then it behaves like a wrong mineral oil, it gets too thin at high temperatures or too thick at low temperatures, or both.
In all cases, following the deadlines will guarantee a long lasting engine. For every dollar you save in your oil changes you probably do 10 dollars of damage to the engine.
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