Can you mix 5w30 and 10w40

Last edited: 23 Jun As said above, if you are only topping up then its OK to use a similar oil. It actually states this in the Haynes manual for a Ford Fiesta, where the oil recommended is 5w30 and it says that 10W40 is OK for top ups. Topper Hitman Joined: 11 Jun Posts: Would you say fully synthetics fall into that category? Much thanks. Lakeland Soldato Joined: 1 Nov Posts: 5, I wanted something a little bit thinner than 10w40 but didnt want to use just 5w 30?

Last edited: 28 Jun As posted above, mixing 5w30 with 10w40 will give you an oil that performs somewhat better in the cold than 10w40, but less good cold than 5w30, and that has a viscosity a bit higher than 5w30 but a bit lower than 10w Mixing different oils will not improve the performance or efficiency of the engine in any way.

The engine will last longer and run better. No, not at all. Now, as far as different grades are concerned, mixing between them isn't something that will damage your engine either. Wenli Bloomfeld Professional. What happens if you use 5w 20 instead of 5w 30? Due to the increased resistance of the thicker 5W - 30 oil, your engine will produce slightly lower fuel economy and horsepower output.

You also risk engine damage when using 5W - 30 instead of 5W - 20 , as the internal engine components are specifically designed to be used with 5W - 20 motor oil. Sole Suriol Explainer. Can you put 15w40 in a 5w30 engine? First, the oil viscosity change won't cause your head gaskets to blow off. The real problem with using 15w40 in place of 5w30 is the increase thickness of 15w Obviously the heavier oil would be a good thing. Daira Sorkin Explainer. What happens if you mix 5w30 with 10w30? Keep in mind oils do not mix if you have 5w30 and add 10w30 it won't give you a blens both oils will stay seperate so you will have a few quarts 5w30 and a quart 10w30 they never mix.

Different viscosities will work fine. Zachery Dierchen Explainer. Can I use 10w 40 instead of 5w40? At operating temperature it is exactly the same. Multi-viscosity oils with a lower W number are specifically designed to flow better, and thus lubricate better, at very low temperatures.

There is no need to use a 5w if the vehicle only requires 10w - Pencho Renk Pundit. Can you mix 5w30 and 5w20 oil? Yes, you can. It is best if they are from the same brand and level of API service to be the same formulas, but they are certainly compatible, even if different formulas and brands.

Florenta Aranburu Pundit. Can I put synthetic oil in a high mileage car? This could result in leaks that cause the engine to burn oil and require you to monitor your oil levels and replace it more often.

It's not accurate to say that you should never use synthetic oil in an older car. Anhelina Renziehausen Pundit. What is thicker 5w30 or 10w40? The 5w30 has a viscosity of 30 at high temperature while a 10w40 has a 40 viscosity at high temperatures. When at high temperatures, the 5w30 oil becomes thinner than the 10w40 oil since 30 is lower as compared to Abarca Cristas Pundit.

Can you mix 5 30w and 10 30w oil?