Quick Answer: Is High Mileage Oil Good Or Bad?

Is it OK to use high mileage oil in a new car?

The one reason you don’t want to use high mileage oil in a newer engine is the seal conditioner.

The seals tend to shrink over time, and eventually they leak.

The conditioner softens the seals and get absorbed by the seal, making it puff back up.

You don’t want your newer, perfectly good seals, to puff up any more..

Do high mileage engines need thicker oil?

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.

How long does high mileage oil last?

The quick-lube chains usually recommend it be done every three months or 3,000 miles, but many mechanics would tell you that such frequent changes are overkill. Indeed, most car owner’s manuals recommend changing out the oil less frequently, usually after 5,000 or 7,500 miles.

Does high mileage oil really make a difference?

High-mileage motor oil doesn’t hurt and it could prevent leaks from starting. … In addition to having seal conditioners, high-mileage oils usually boast more detergents designed to clean out sludge inside the engine, plus other additives meant to reduce wear on 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.

What’s the difference between high mileage oil and regular oil?

High-mileage oils have ingredients to take care of older engines, like conditioners, seal swells, antioxidants, detergents and wear or friction additives. … The higher-mileage oils are formulated with seal conditioners that increase flexibility and restore shape, which can help prevent leaks in the long run.

What’s considered high mileage for oil?

Some people might consider switching to a high mileage oil at 200,000 miles, while others may want to change to a high mileage oil at 80,000 miles. For the average driver, anything over 100,000 miles could safely be considered a high mileage vehicle.

Can I mix 10w40 with 5w30?

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 10w40.

Is synthetic oil better for high mileage cars?

High mileage oil is designed for vehicles with more than 75,000 miles. … As a rule of thumb, most new cars require synthetic oil. Older cars generally run well with conventional oil, unless your vehicle has more than 75,000 miles on it, in which case high-mileage oil is recommended.

Is 5w30 good for high mileage?

1. Valvoline 5w30 – Editor’s Choice Best Synthetic Blend High Mileage Oil. … Having a large market share also allows Valvoline to cater to all niches, but we think that this is the best all-around motor oil for a high mileage engine that we saw. That is why the Valvoline 5w30 is our Editor’s Choice best high mileage oil.

Can I stop using high mileage oil?

Yes, you can switch to using a synthetic motor oil. … High mileage oil has a component or two that can help, but it’s mostly marketing. Switching to a full synthetic it will do better than with a mineral oil.

What type of oil is best for high mileage cars?

5 Best Motor Oils for High Mileage Engines#1 – Mobile 1 High Mileage Synthetic Oil.#2 – Royal Purple HMX Synthetic Oil.#3 – Mobile Super High Mileage Synthetic Oil.#4 – Castrol GTX High Mileage Synthetic Blend Oil.#5 – Pennzoil High Mileage Synthetic Blend Motor Oil.

Is it bad to mix engine oil?

The good news is that mixing different types of oil it will not harm your engine in any way in the short run. Most synthetic and semi-synthetic engine oils are based on regular oil and are compatible. … Now, as far as different grades are concerned, mixing between them isn’t something that will damage your engine either.

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.

Can I mix high mileage oil with regular oil?

Mixing Motor Oil According to Mobil Oil, it should be fine to mix oils. … So, if you are low on oil, don’t be afraid to add a quart or two of synthetic oil if you are using regular oil or even regular oil if you are using a synthetic.