Quick Answer: Can I Mix 5w30 With 10w40?

Will 10w40 hurt a 5w40 engine?

10w40 is thicker than 5w40, ONLY when cold.

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-40 if the vehicle only requires 10w-40..

Should I use thicker oil in a high mileage engine?

A: Yes. This is a practical method to improve oil pressure in an older, high-mileage engine. The slightly thicker oil film from the heavier base weight oil – 10W – can help protect worn engine bearings as well.

What happens if I use 10w 30 instead of 5w 30?

Also, 10W30 means the oil will be a little thicker at same lower temperatures, and will then protect the engine the same as 5W30 at higher temperatures. … Using 10W30 in very cold conditions may cause damage to your engine.

Will 10w 30 oil hurt a 5w30 engine?

Most oils will mix perfectly, provided they have a similar synthetic. Therefore, there is no problem in mixing 10w30 and 5w30 since one will be topping up. Mixing the viscosity of oils will not have any effect on the engine. 5w30 and 10w30 engine oils have close viscosity, and thus there is no harm in mixing them.

What happens if I mix 5w20 and 5w30?

You can mix a 5W20 with a 5W30 oil with minimal amount of issues provided it the same manufacturer and the same API classification. … I would suggest just getting the oil changed.

When should I use 10w40 oil?

When to Use 10w30 vs 10w40 Using 10w30 oil in cold weather will help reduce excessive oil temperatures and drag as the engine warms up. Using 10w40 oil in the summer will help the oil stick to internal components in high temperatures, avoiding the wear and tear from metal-to-metal contact between moving parts.

Which oil is thicker 5w30 or 10w40?

A 10w-40 motor oil is a thicker oil at startup than a 5w-30 motor oil. Therefore, 10w-40 oil clings to the engine’s moving parts more than the lower viscosity 5w-30 oil.

Will thicker oil damage my engine?

Not only that, but the engine will waste energy pumping the thicker motor oil, reducing fuel economy. Since thicker oils don’t transfer heat as well as thinner oils, operating temperatures will increase, too, possibly leading to accelerated chemical break down and harmful sludge and deposits.

Is it OK to mix different weights of motor oil?

It is always advisable to not mix motor oil brands, however, different viscosity grades of the same brand motor oil are compatible. … But there’s absolutely no danger about incompatibility resulting from mixing engine oils,” Miller says. “We’ve tested all of our grades and brands, and we haven’t observed any problems.”

What happens if you mix 10w30 with 10w40?

You will be fine with that. They will mix right in with each other and no harm will be done. Even if you were to mix syn with conventional you’ll be fine. If you were to labratory test your oil it will read out as not a true 10w-30 but no harm will be done.

Can I mix 5w40 and 10w40?

Mixing the two negatively impacts the properties of both. Just do an oil change asap and you’ll be fine.