Introduction to High Mileage

In basic terms, high mileage oil is exactly what it sounds like, oil made for engines that have put more miles on the odometer. Most high mileage vehicles are considered to have been driven 75,000 miles or more. Even with regular oil changes and maintenance care, certain components in your vehicle may not perform as well as they should. This is why high mileage oils contain special additives to prevent any aging issues in your vehicle that are not addressed with normal engine oils. It helps prevent older seals and gaskets from becoming fragile and causing leaks. 

High mileage oils are often based on either a full-synthetic oil or a synthetic blend (a mix of synthetic and conventional oils). More information on the different types of oil can be found here.

When To Use High Mileage

Typically, older engines have an issue with oil leaking due to degradation of engine gaskets, oil pan leaks, or worn-out seals. The more miles you put on your vehicle, the more likely your engine is to suffer from complications such as premature engine failure and oil leaks. The ingredients in high mileage oils include additives and seal swelling agents that reduce oil leaks. 

No more oil spots will be left in your driveaway!

Aside from preventing oil leaks, high mileage oils prevent viscosity break-down within these older engines. High mileage contains anti-oxidant additives which counteract any sludge that may be accumulating within the engine. Since the engines are older, the oil needs to stay thicker for longer to protect vital engine parts. High mileage oils use a viscosity modifier so they will not lose their thickness too soon. 

Some other signs that may indicate it is time to make the switch would be a rattling noise coming from your engine, a decrease in gas mileage, a decrease in throttle response, your engine being slow to start on a cold day, and increased oil consumption. 

How Often Should High Mileage Oil Be Changed?

Exactly the same. Your oil change interval can stay the same as it has been in the past and there should be no need to change your maintenance routine. An engine that has been well taken care of throughout its life can handle a longer interval between oil changes, but it is always best the check with your vehicle’s owner’s manual and follow the manufacturer’s recommendations. 

For owners of older vehicles, drivers should check the oil levels around once a month to ensure they are not traveling low on oil, which can lead to ill-timed engine damage. 

Is it Harmful to New Vehicles and their Engines?

A major difference between high mileage oil and the regular stuff is the number of conditioning agents to seal parts over your engine that may have degraded over time. At Oil Changers, we do not recommend a customer considers high mileage until the odometer reads 75,000 miles or their vehicle continually has issues with oil leaks.