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Kwok Cheik Chong

What happens if you mix 10W30 and 10W40 oil?

Dominic Tramonte  Follow

No. Use only the approved type of 2-cycle oil 8n your engine.

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Amelia James  Follow

You certainly can. It will just change the low temperature pumping point. Ideally they will be both from the same brand to get the same formulation, but they will be compatible anyway.

This is common with people who buy a case of oil or large bottle, and have some left over that they want to use.

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Anil de Silva  Follow

Wow. two extremely wrong answers. Or are they meant to be satire?

Yes, you can mix them. They will mix perfectly. In warm climates, they will act very similarly. Both are the same viscosity at operating temperatures.

But which was recommended by the manufacturer of your car?

  • If they originally recommended 10W-30, they you can use 5W-30 or a mixture.
  • If they originally recommended 5W-30, your mixture will not pump as well at very cold temperatures.

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Claudio Giomini  Follow

You could put chicken fat into your engine. Question is “should you, not can you”? Why not just use the correct weight?

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David Bradbury  Follow

10W40 is thicker. It starts at 10W which is thicker than 5W and moves up to 40W which is thicker than 30W. The 10W40 has been used for decades as the standard oil for many cars. The 5W30 is newer and many times is Synthetic. Many modern cars with closer tolerances use the 5W30 oil.

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Bruce M Wentworth  Follow

“SAE 10W-40” typically designates a ‘multi grade’ engine oil, having the viscosity characteristics of an SAE 10W oil, at low temps, and an SAE 40 oil, at operating temps. Multi grade oils are recommended by most engine manufacturers for use in a wider range of ambient temperatures than single grade oils. General advice is to use the oil recommended by the engine manufacturer for the prevailing ambient temp conditions.

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Aldino Piva  Follow

You get 10W35.

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Cade Ellis  Follow

Regardless of what you drive or ride you DO NOT want to use an inferior motor oil. Buy the best or one of the top oils at least

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Blessing Benjamin  Follow

Nothing. In extremely cold weather, it might be a little more difficult to start the vehicle but that’s about it. In extremely hot weather, your engine will be more protected from heat-related failure.

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