Will High Mileage Oil Hurt a New Car

High mileage oil is not usually suitable or beneficial to all cars, therefore it is advisable that before you choose to use it in your car, you check the car’s owner’s manual.

In most cases, car owners are advised to use high mileage oil under certain conditions, conditions such as; if the engine parts are wearing out, the car has covered a particular mileage, or when there is a leak.

It is also advisable to use high-mileage oil in older cars and not in new cars. Why is this so? Will high-mileage oil hurt a new car?

No, high mileage oil will not hurt a new car but it’s hardly beneficial to it. 

Can you Use High Mileage Oil in your New Car?

Yes, you can use high-mileage oil in your new car but it is not advisable to do so.

High mileage oil is said to contain additives and seal enhancers that help to reduce leakages. It also helps to reduce oil spots.

Asides from the composition of high mileage oil, you may not really be able to tell it apart from other engine oils since they all most often have a similar package.

However, despite the similarity in package, you should be able to differentiate high mileage oil by its concentration.

Using high mileage oil in a new car won’t necessarily cause any damage to it but it won’t be beneficial to the car either, it is best suited for cars with 75,000 miles and more. As a matter of fact, manufacturers do not recommend using high-mileage oil in a new car.

Will High Mileage Oil Hurt a New Car?

No, high mileage oil will not hurt a new car.

High mileage oil will be useless in a new car because it won’t be serving its main purpose which is helping to prevent the aging of seals and gaskets, to prevent leaks and bristling of the engine parts.

All parts of an engine are still new when you are purchasing it newly therefore other than helping to ensure lubrication in the engine, high mileage oil will not do anything extra.

If you have decided not to use high mileage oil in your new car, let it not be because you think it will harm or damage your car but because it doesn’t benefit the car in any way plus it can be expensive.

When Should You Use a High Mileage Oil?

Knowing when to use high mileage oil is important as it helps you get the full benefit out of it. Therefore, we will be considering when you should use high mileage oil.

When using a High Mileage Vehicle

High mileage vehicles are specifically designed to use high-mileage oil, using anything other than this may cause leakage problems because the oil will be incompatible with the engine seal type.

Using synthetic oil for instance in a high mileage vehicle may also clean out buildups that are meant to seal a leak. Therefore, it is recommended that you use only high mileage oil in your high mileage vehicle.

The Car has 75,000 Miles Under its Belt

If you are not using a high mileage vehicle it is advisable to wait till the car has been used for over 75,000 miles or close to.

A car that has gone over 75,000 miles already have some of its part getting worn out, therefore using high mileage oil will prevent internal and external oil leaks, it also helps the engine O-rings, seals, and gaskets to swell.

Note, that waiting till the car is well over 75,000 miles is totally up to the car owner and the condition of the car.

You want to Keep Your Engine Healthy

If you think there is a need to keep your engine healthy because it has been in use for some time or for whatever reason, one way to do this is by using high mileage oil.

High mileage oil contains additives and enhancers that help to keep the engine healthy thereby making it last longer.

When there is a Leak

If you start noticing oil stains underneath the car when it is parked then there may be a need to switch to denser motor oil i.e. high mileage oil.

Most times when there is a leak, it could mean some parts of the engine is loose, to get them back in position and also stop the leakage, you should use high mileage oil. High mileage oil has properties that help to seal leaks and gaskets.

What Happens if I Use High Mileage Oil in a Low Mileage Car?

Using high mileage oil in low-mileage cars will not necessarily harm the car but can sure do a number of things, just like when it is used in new cars.

Here are some things that will most likely happen when you use high mileage oil:

  • It Prevents Wear and Tear of Engine Parts: One thing that will most likely happen when you use high mileage oil in low mileage cars is it helps to prevent wear and tear of the engine parts. Over time, with use engine parts, tend to wear out, so as a preventive measure, you can choose to use high mileage oil rather than waiting for the parts to wear out and repair or replace them.
  • It Keeps it Performing Optimally for Long: High mileage oil in low mileage cars will keep the car performing effectively for much longer especially if the car has seen better days. As cars age, there tends to be a decline in performance whether low or high mileage car, using high mileage oil is a good way to keep the car performing well.

Does it Hurt to Mix High Mileage Oil with Regular?

No, it doesn’t hurt to mix high mileage oil with regular oil.

It is possible to mix high mileage oil with regular oil and no, mixing them will not hurt the engine nor will the engine benefit from the mixture.

If you have decided to mix high mileage oil with regular oil, know that there won’t be any difference and if there is it will be hardly noticeable.

If your intention for mixing high mileage and regular oil is to increase the engine performance you might as well just stick to either of the oil (high mileage or regular) depending on your engine type, the car’s mileage, or even the manufacturer’s oil recommendation.


If you are not sure of when or whether to switch to high mileage oil in your car, check your owner’s manual or consult with your mechanic as you will want to get the most out of any oil you put in the engine.