I own a 2018 Kia Soul (Base Model), which has the 1.6L I4 engine. It is NOT the turbo version nor the diesel version. It is also not the 2.0L version. Frankly, I am very confused as to what weight of oil to use. I am attaching a screenshot of what the owner's manual says about recommended oil viscosity. It is vague, to say the least.
For reference, I live in a hot climate (Texas), and the temperatures usually range from 15C - 35C (or higher in the summer). Usually winters do not go below 0C. The chart they use seems to indicate that I can use either 5w-20, 5w-30, or 10w-30 (and there are even more options for the Turbo owners!). I noticed that the comment on the left-hand side also says that "higher viscosity is recommended for proper lubrication in hot weather". This is contrary to everything I understand about engine oil. I would love to switch to the _W-30 oils because then I can use the same oil for both of our cars, but I am concerned that could be harmful to the engine. I have been using 0w-20 oil based on a recommendation I saw online somewhere, but now I can't find that anymore.
Essentially, my question is this: Can I switch from 0w-20 to 5w-30 without harming the engine? Also, why would a manufacturer be so vague about the recommended oil weight? Aren't engines designed to work with a specific weight?
I agree, this is very confusing.
Check the oil cap in the engine bay. Use that viscosity for your car.
The cap says 5w-20. I guess I can't go wrong with that. Thank you!
I noticed that the comment on the left-hand side also says that "higher viscosity is recommended for proper lubrication in hot weather". This is contrary to everything I understand about engine oil.
Viscosity = thickness
so higher viscosity = thicker oil.
In warm weather 10w30 oil will have higher film strength than 5w30 (on startup)
But this is less of a concern with modern synthetic oils.
I don't see 0w20 anywhere on the chart. The OEM isn't being vague. They're just telling you what will work in the car. If you're in a warm climate use 10w30. If it gets below 0F where you are, then use 5w20 or 5w30 (whichever is available). Pretty straightforward.
