Is High Mileage Oil Good Or Bad

Most vehicle owners get confused when they go shopping for engine oil in a specific auto-parts store, seeing the wall of lubricant in front of them. They can find a dozen of engine oils that come from different brands with different price tags. Some oils claim they will enhance engine protection against wear & tear. And some of them promise to improve engine performance. 

Therefore, there are two types of oils- synthetic and conventional. Plus, some oils are tagged as high mileage oils for old engines. All of these are enough to lead you to your local car dealership for service. 

Now, let’s come to the point. You have an old car with 75000 miles or more. Most manufacturers recommend switching to high mileage oil at this point. But you have a question in mind- Is high mileage oil good or bad? To know the answer, read between the lines. 

What Is High Mileage Oil?

High Mileage Oils are generally the oils that contain special additives like seal conditioner, antioxidant, and detergent to meet the need of your old or high mileage engines. In simple words, high mileage oil is specially formulated to address the problems of your car that hit the 75000 miles mark or more. 

Keep in mind; high mileage is a marketing term every oil manufacturer uses to sell their oil quickly at higher costs compared to regular motor oils. Though high mileage oils contain more additives than regular synthetic oil, you can still use the synthetic oil for your old or new vehicles. 

High Mileage Oil Vs Synthetic

There are distinct differences between high mileage oil and synthetic oil. First off, manufacturers produce high mileage oils by blending synthetic with other petroleum-based oils and adding special additives like conditioner seals, detergents, and antioxidants. On the other hand, we get synthetic oil by mixing synthetic with conventional oils. 

Secondly, most manufacturers advertise that high mileage oils contain special additives, which deliver unmatched protection against engine wear & sludge for older engines. In contrast, synthetic oils are never advertised; they contain such additives as high mileage oils. It doesn’t mean synthetic oils don’t include any additives that fit your old car engines. 

Thirdly, both synthetic oil and high mileage oil are good for your new or old car engines. They will lubricate your engine to prevent sludge, wear, and thermal breakdown. 

Finally, high mileage oils are a bit pricey compared to regular synthetic oil.

Is High Mileage Oil Worth It?

The question is- is the high mileage oil really worth the extra cost? Yes, it does. If you have a high mileage car or an old car, high mileage oils lubricate every moving part of your engine so they operate smoothly. Plus, it prolongs your engine life by withstanding wear. 

However, some manufacturers recommend you switch to high mileage oils at a specific mileage point. But we suggest you not go for high mileage oils until you can see any signs of engine wear.  

Over time, every mechanical part starts loosening- even your door handles. When your engine gets old, seals, gaskets, and non-metal parts begin to decay. And the high mileage oils are specially formulated with seal conditioners. Due to these, high mileage oils increase flexibility and restore shape, preventing leaks in the long run. 

The bottom line is- high mileage oils are specially formulated for older engines that are beyond their warranties and hit the 72000-150000 miles mark. It would be best to pour high mileage oils into your car when you notice rattling or see a leak. 

Some mechanics don’t think high mileage oils are worth the price if your engine still runs well. They recommend you switch to high mileage oil when your vehicle starts dropping gas mileage, reducing throttle response, and spewing white or blue smoke from the exhaust

When to Use High Mileage Oil?

Most manufacturers recommend using or pouring high mileage oil into your car when you reach the 75000 miles mark. At this point, your old car may get benefits from high mileage oils as they prevent oil leaks and provide better engine protection against sludge & wear. 

But we recommend you not switch to high mileage oil if you don’t have any problems with your engine. It doesn’t make any sense to spend extra bucks when your engine performs the best with the oil you are using currently. If you hit 75000-15000 miles on your engine and still notice no oil leaks, continue to use the oil you are pouring into your car. 

High mileage oils may get you some extra thousand miles out of engine wear and tear. And this is the biggest benefit you will gain using high mileage oils. 


Yeah, high mileage oils are good both for new and old cars. But every manufacturer suggests switching high mileage oil when you reach the 75K miles mark. 

But we recommend you stick with the regular oil if you don’t face any problems with your engine. 

About John M

John contributed as a technical head at an automobile company just 2 years after his post-graduation in Automobile Engineering. He loves to lead a free life, so he left his job & started blogging. Now, he does research on every automotive problem, part & product and seeks a better solution & best products & shares his findings with his readers to help them as well as to minimize their struggle.

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