Quick Answer: What Happens If I Use 15w40 Instead Of 5w30?

Do high mileage cars need thicker oil?

High-mileage motor oil doesn’t hurt and it could prevent leaks from starting.

Some mechanics recommend switching to a thicker (higher viscosity) oil — such as 10W-30 full synthetic oil instead of 5W-20 full synthetic — or using oil additives to stop leaks..

Can you put 15w40 diesel oil in a gas engine?

Diesel oils perceived as “tougher” Others lean toward higher-viscosity oils to protect against wear. Some want to run a 15W-40 oil in their gas engine, and it’s often easier to find a 15W-40 or similar viscosity of diesel oil than a gasoline motor oil. Others favor the increased detergency of diesel oils.

When should I use 15w40 oil?

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 oil is thicker 5w30 or 15w40?

E.g. 5W-40 is thinner when cold than 10W-40, but 5W-30 and 5W-40 are both within the 5W range when cold. The number after the – specifies that the oil’s viscosity when hot falls into a specific range. So 5W-40 and 15W-40 both fall within the 40 range when hot, but 5W-40 is thicker than 5W-30 when hot.

What happens if I put 10w30 instead of 5w30?

Your oil is a little thicker when cold. No damage will happen. … The 5W and 10W defines how the oil will flow at 0 degrees. At operating temperature, there will be a completely insignificant difference between the two.

What temperature is 15w40 good for?

“Diesel has the widest performance range with 5W40,” says Mark Betner of Citgo. “Its starting temperature range is down to minus 22 F (compared with 15-plus with 15W40) up to 122 degrees F (same as 15W40).

Can I use 10w 40 instead of 15w40?

Viscosity or thickness of the oil increases with rise in temperature. 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.

Can I use 15w50 instead of 15w40?

oil is not this accurate, 15w50 is heavier than 15w40 even when cold. heavier oil will not have better temp protection. in fact, it will keep more heat in the ingine. … thicker oil will have a harder time going through, if temp is you worry heavier oil is not the way to go, you need to go to synthetic.

Is mixing 5w30 with 10w30 bad?

Mixing different oils will not improve the performance or efficiency of the engine in any way. … 5w30 and 10w30 are both 30 weight oils and the exact same thickness in your engine when it is at operating temperature. The 5w30 is better because it thickens less when cool or cold. Thinner oil gets to the top end faster.

Which is thicker 5w40 or 15w40?

15w40 is slightly thicker at high temperature. Cold is the same. … 5W40 oil is thinner than 15W40.

What does the 15w40 mean on engine oil?

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.

Can you put 15w40 in a 5w30 engine?

No, you won’t blow a head gasket, but 15W40 is too heavy an oil to use where 5W30 is required. Besides, most 15W40 oils are gor diesel engines. No, the head gasket won’t blow off.

What is the best 15w40 oil to use?

For anyone who needs a good diesel motor oil to help boost their engine’s performance and fuel efficiency, we recommend the Royal Purple 15W-40 Oil. If you want to save some cash and still invest in one of the best diesel oil’s on the market, go for the Shell Rotella T6 Synthetic Diesel Motor Oil 5W-40 CJ-4.

Can I use 10w 40 instead of 5w30?

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.

Can I use 20w50 instead of 15w40?

Can I use 20w50 oil as a top up to my 15w40 engine oil? … It is best to use the same brand, type and weight of oil you put in at the last oil change. Unless you are at the fringes of temperature range for the 15w-40 oil, putting the 20w-50 in isn’t going to change the viscosity of the oil enough to damage anything.

Is 5w30 better than 15w40?

Probably not. 15w40 is usually used in diesel engines and has a much different additives profile. 5w30 is usually used in gasoline engines. … Gasoline oil doesn’t have the antiwear additives diesel oil does, leading to faster wear on your engine.

Can I use 15w30 instead of 5w30?

Honestly you will be fine. An ’03 will have some miles on it and the 15w-30 will no harm your engine. After the 16–17 years of life in that vehicle the oil clearances will have gotten a bit bigger from normal wear and tear and you might not burn as much now. When should I use 10W-40 motor oil?

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.