Can I mix 5w40 instead of 5w30?

Conclusion. So, can you mix 5W30 and 5W40 oil? Just like mixing full synthetic with semi-synthetic oil – mixing different viscosity such as the 5w30 and 5w40 is not a bad idea, especially if you are running low on oil. However, doing so is not ideal if you want to reap the benefits of what the motor oil brand intends.

What oil do you put in a Toyota Yaris?

Engine oil: what the digits mean

What does 5w40 mean in motor oil?

5w40 motor oil has a winter viscosity grade of five, meaning it’s less viscous at very low temperatures, compared to, say, 10w40. It has a hot viscosity grade of 40, which means it is just as viscous as 10w40 at high temperatures but less viscous than oils such as 15w50.

Can you put 10w40 in a 5w40 engine?

Yes. 10w40 is thicker than 5w40, it will not lubricate all the parts that need lubricating from cold. You’d probably be better of leaving the old oil in there than swapping the correct (but old) oil for incorrect (new) oil.

What happens if you mix oil grades?

What happens when you mix different oil brands? While it is not recommended to mix various brands of motor oil (such as Valvoline, Castrol, Total or Mobil 1), it will not cause any damage to your engine. What is far more important is to stick with the same oil viscosity as recommended by the car manufacturer.

Can I put 10w40 instead of 5W-30?

Your vehicle does not use 5W-30 oil. The recommended oil viscosity for your vehicle, according to Kia documentation, is 10W-40. If you drive the vehicle in exceptionally cold weather, well below 32 degrees, you can use 5W-30 oil but even 10W-40 is still perfectly OK to use if outdoor temperatures are below freezing.