Quick Answer: What Is The Difference Between 10w 40 And 15w 40 Oil?

Can I mix engine oil viscosity?

THE ANSWER IS NO.

Even if two different brands of oil have the same viscosity, you still should not be mixing them together.

(Why anyone would even consider doing this in the first place is something we cannot comprehend..

Can I use 5w30 instead of 15w40?

If the manufacturer’s recommendation for your engine allows you to use 5W30 oil, you can use either 5W30 or 15W40. If your engine only calls for 15W40, please only use that grade of oil; big engines are too expensive to risk.

Can I put 15w 40 in my car?

No but you might do more damage than good forcing heavier oil through engine designed for thinner oilif you want a more heavy duty oil as 15w40 is classified as a diesel oil look at Shell Rotella T or Ford/Motorcraft 5w40 full synthetic.

What is the best engine oil for hot weather?

Top 10 Best Motor Oils for Hot Weather Reviews (summer)#8. … #7. Pennzoil Platinum Motor oil for hot weather.#6. Mobil 1 (120766) Motor Oil for hot weather.#5. Valvoline Advanced Car oil.#4. Valvoline 10W-40 Synthetic Motor Oil.#3. Castrol 03084 Motor oil for hot weather.#2. AmazonBasics Full Synthetic Motor Oil 5W-30.#1. Castrol 03057 Motor Oil for hot weather.More items…•

What does the 15 in 15w40 mean?

The first number 15W is the viscosity of the oil at cold temperature, and the second number 40 is the viscosity at 100 °C. The 15W40 designation means that the oil is a multigrade oil. It has the viscosity of 15W when cold and the viscosity of SAE 40 when hot. This means that one type of oil works in all temperatures.

Is it OK to use 15w40 instead of 10w40?

A 10W40 oil will be thicker in the cold than 15W40 oil, but they will have the same viscosities at higher temperatures. The winter viscosity number dictates cold-start performance. … 10W40 oil will perform cold starts better than 15W40 oil.

Does 10w40 hurt 5w30 engine?

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.

What is 10w 40 oil for?

The lower the “W” number the better the oil’s cold temperature/cold start performance. The 40 in a 10w-40 simply means that the oil must fall within certain viscosity limits at 100°C. This is a fixed limit and all oils that end in 40 must achieve these limits.

Is 15w40 good for petrol engines?

15w40 is typically used in diesel engines. … There are other additives to address issues particular to diesel engines but aren’t detrimental to gasoline-powered engines if the oil is used in them.

Can I use SAE 40 instead of 10w40?

So to answer your question, both 10W-40 and straight 40 will give the same protection at operating temps. The 10W-40 will allow better starts in cold weather where as the straight 40 will cause a slow cranking in cold weather.

Is it OK to mix 10w30 and 15w40?

Absolutely no issue whatsoever mixing them; they are both approved for use in the Dmax.

Is 10w40 synthetic?

Semi-synthetic oils such as 10W40 have long been the standard. Their base is refined crude oil, which is then blended with additives.

Which engine oil is best?

Top 10 Best Synthetic Motor Oils 2020Castrol 03101 EDGE. View on Amazon. … Motul 8100 X-cess Oil. View on Amazon. … Valvoline SynPower Oil. View on Amazon. … Liqui Moly 2041 Motor Oil. View on Amazon. … Schaeffer’s Synthetic Engine Oil. View on Amazon. … Shell Rotella T6 Engine Oil. … Mobil 1 Synthetic Oil. … Pennzoil Platinum Oil.More items…•

What is 15w 40 oil used for?

ADVANTAGE 15W-40 HEAVY DUTY DIESEL ENGINE OIL can be used with complete success in over-the-road diesel trucks, off-highway diesel equipment, farm tractors, and passenger cars and light trucks with diesel, turbo-charged diesel engines, or gasoline engines and is backward compatible with previous API Oil Categories.

Which is better 10w30 or 15w40?

Because 10W-30 is thinner than 15W-40 oil, its film strength can be weaker and it can be more prone to oxidation. Therefore, high quality additives are needed to compensate for those weaknesses in order for a 10W-30 engine oil to protect as well and last as long as a 15W-40.

When should I use 10w 40 oil?

Overall the 10W30 will be the more appropriate oil for cold weather and non-performing engines while 10W40 is perfect for warmer temperatures and older vehicles. But, if you are still not sure what to use, talk to your local mechanic or check the vehicle’s manual.

What is the difference between 5w 40 and 15w 40 oil?

Viscosity is a fluid’s resistance to flow. … Both will have a viscosity of a 40 grade. That cannot be said for both oils during the dead of winter. The 5W-40 will have a lower viscosity when the engine is started than the 15W-40; consequently the 5W-40 will start easier and lubricate quicker in the cold than the 15W-40.

Is 10w 40 too thick?

Multi-grade oils could stay as close to the optimum viscosity over a range of temperatures – not too thick when it is cold and not too thin when it is hot. … The difference between 10W-30 and a 10W-40 is the high temperature viscosity. Obviously, a 10W-40 is thicker than a 10W-30 at high temperature.

What is the best 15w40 oil to use?

Top 5 Best Diesel Engine Oil of 2020Castrol EDGE Extended Performance 5W-30. Castrol is a name synonymous to quality and high-performance. … Valvoline 5W-40 Full Synthetic Diesel Engine Oil. … Royal Purple API-licensed Motor Oil SAE 15W-40. … Shell Rotella T4 Triple Protection 15W-40. … Mobil 1 120760 Synthetic Motor Oil 0W-40.

Does gas in oil damage engine?

Gas can be very expensive so it’s not ideal to just waste it. Another reason this is a problem is because when gas and oil mix, this causes the oil to lose its ability to lubricate the engine parts. When oil can’t do its job properly, these parts start to create a lot of friction and then the engine could overheat.

Can you run 10w30 in a diesel?

The lubrication manuals of all the major brands of on road heavy diesel engines allows for using 10w30. So worrying about OEM recommendation is not an issue.