Best High Mileage Engine Oil for Car’s Over 100k Miles

We all know how much motor oil is vital for an internal combustion engine to function adequately. It lubricates almost every moving part, reduces friction and the wear of the engine's internals, and helps cool down the whole unit. And that is just the beginning of the story. Older mechanics often say that engine oils are more important than fuel. If you run out of fuel, you just put some of it in the tank and are good to go, but if you run out of motor oil, your engine is ruined and you're not going anywhere. Today, we will explain all the basics of engine oil and help you decide what lubricant you need for your car.

What Is Motor Oil?

Motor oil is an engine lubricant designed to lubricate the engine's moving parts, mainly pistons, crankshaft, camshaft, and valve train. It is a blend of various chemicals, organic or synthetic, which enhances viscosity and durability under extreme conditions and high and low temperatures. Without motor oil, the car engine wouldn't be able to operate. In case of a sudden loss of engine oil, engine sizing is imminent and often fatal for the whole motor. Among the chemicals used for lubricating, motor oil consists of anti-corrosion components, various detergents, and viscosity improvers designed to improve performance and reduce system wear.

How Often To Change The Oil (Time And Mileage)

Due to engine and motor oil technology improvements, modern cars can have relatively long oil change intervals. Most current models can go 10 to 20.000 miles on a single oil change. Of course, the exact length of the oil changing interval depends on several circumstances such as engine type, use, diesel or gasoline, mileage, etc.

Changing the oil in due time always helps your engine since it provides fresh lubrication, prolonging the motor's life and reducing wear. Even if you do it more often than required it will not harm your car. However, if you forget to change your oil and go way over the recommended interval, it will reduce the performance of your engine and increase the wear of internal components.

If you own a new or newer vehicle with fewer miles, we recommend following the manufacturer`s instructions and changing the oil accordingly. However, if you own an older car with high mileage, we recommend changing the oil at least once a year and at around the 5 to 10,000 mile mark. Older engines benefit from regular oil changes and this simple procedure will help keep them running for long.

Types Of Motor Oil

The primary way to differentiate motor oils is by the formula used in production. There are three different formulas - mineral, synthetic, and synthetic-mineral blend.

Mineral Motor Oil

Mineral motor oil is a petroleum-based product that is mostly made from natural ingredients. This type of oil used to be the standard of the industry but in recent years, car manufacturers moved to synthetic or semi-synthetic oils.  Mineral motor oils are not complicated to produce but are not for use in high-performance engines.

Synthetic Motor Oils

Most motor oil produced today is synthetic since those formulas provide the best protection, lubrication, and wear protection. Synthetic oil is superior to minerals, which is now the industry standard. It is more expensive than mineral but far better, especially for extreme climate use, vehicles that operate under heavy load, or high-performance applications.

Synthetic-Mineral Blend

This is a mix of conventional mineral oil with synthetic oil. They offer similar benefits that synthetic motor oils provide, making them superior to mineral oil, but at a lower price. Synthetic-mineral blends, however, cannot reach the heights of performance that only the best synthetic oils can.

Motor Oil Brands

As you probably know, there are numerous motor oil brands on the market and all of them offer quality products for various purposes and engine types. The most common brands used today are Mobil, Castrol, Valvoline, Royal Purple, Quaker State, Pennzoil, etc. Also, several car manufacturers also produce engine oils designed to work best with their cars.

However, in recent years there have been reports of counterfeit motor oils appearing on the market. The package looks the same as the label, but the oil is of extremely poor quality and can seriously damage your car. So, when buying some brand name oil, get it from a known vendor and always check the packaging and declaration.

Motor Oil Prices

As an extremely important engine component, motor oil comes in various prices and packages. Most oils start at around $10 for 1 quart but can be much more than that if you need special or high-performance oil. You can get packages of 1 or 5 quarts, the amount you need for an average oil change, or even big barrels of oil, which car shops and service stations commonly buy.

Synthetic Vs. High Mileage Oil

One of the common questions, if you own a high mileage car, is whether to use full synthetic or high mileage motor oil. There is no simple answer since it depends on the condition of your engine.

The main difference between regular synthetic and high-mileage oil is the formula. In the case of high-mileage oil, it is enhanced with detergents, sealers, and additional lubricants. This is made to provide old engines with better protection and keep them operational even with extensive wear. However, if your car doesn't leak or burn oil, has steady idle, and starts quickly in cold temperatures, you don't need high mileage oil as regular synthetic will do just fine.

Should I Use High Mileage Oil?

After a hundred or so thousand miles on your engine, engine internals display a certain level of wear after millions and millions of revs over the years. Moving parts like crankshafts, pistons, valves, camshafts, and so on are no longer precisely fitted inside the engine block or head. The car loses compression and therefore performance and fuel economy. In other, simpler words, the car is old and tired.

However, an oil change can help, and oil manufacturers offer special oils for high-mileage engines designed to bring life back to old powerplants. High mileage engine oil is a special type of lubricant designed as semi-synthetic oil enhanced with several other chemicals to improve lubrication further, stop corrosion, and help reduce oil consumption and leaks known to appear on older engines.

Also, those types of motor oil have more detergents than regular which helps clean the engine from the sludge buildup over the years of use. As you expect, those high-mileage engine oils cost more than regular ones but are they worth the investment? If you have an old engine that burns oil or have a severe oil leak problem, you should try to fix it with high mileage oil designed to reduce such issues. However, if you have a high mileage engine that runs just fine, and doesn't burn or leak oil, then you should stick with regular oil simply because your engine doesn't show the signs of severe wear.

What Is The Best Oil For My Car?

Since numerous formulas, viscosity indexes, and manufacturers are on the market, choosing the right oil for your car can be difficult. However, the best way to determine what oil to use is to refer to your car's factory specifications. Use the exact oil that the car manufacturer equipped your car with. Never mix different oil viscosities or change the type without consulting the mechanics. Changing from mineral to synthetic or putting different viscosity oil can seriously damage your engine.

Of course, if you tuned your car to deliver more performance, you need to upgrade to some high-performance oil.

Best Motor Oil For High Mileage Engines

Fresh oil inside your old engine will rejuvenate the whole engine in minutes. It is a fast, cheap, and very effective way of bringing new life to old and tired powerplants. (Make sure you dispose of your used motor oil properly!)

Here are some of the best oils available on the market which are designed especially for old engines with a lot of miles on them and will make your car run as new after just one oil change (granted you change your oil filter, too!).

Valvoline (VV150-6PK) MaxLife 10W-40 Higher Mileage Motor Oil


The name tells it all and not only is this the product of a well-known and respected company but it is designed especially for high-mileage engines. This synthetic oil performs better than the old mineral ones with additives that help close the seals and prevent the oil from leaking from your engine. It also helps remove the engine's deposits and sludge.

Buy Valvoline 10W-40 MaxLife High Mileage Motor Oil - 5qt (782482)

Pennzoil High Mileage Vehicle Oil


Another quality product from Pennzoil is affordable and very good in preserving your engine and bringing back lost performance and agility. Like similar products, this is also an improved synthetic formula that will reduce wear, help seal the cracks, and stop leaking. Also, this oil will have longer intervals and clean the engine's internals.

Buy Pennzoil 550045217 5 quart 10W-40 High Mileage Motor Oil (SN Jug)

Mobil 1 45000 5W-30 High Mileage Motor Oil


Mobil 1 is also a well-respected company in the oil business and their products are often the best on the market. The exciting thing about this product is its 5W viscosity index, which means that this is more dense oil than the rest and is suited for engines with extreme mileage since it will seal it better. So if you have a million miller, this oil is for you.

Mobil 1 45000 5W-30 High Mileage Motor Oil - 1 Quart (Pack of 6)

Castrol 06470 GTX 20W-50 High Mileage Motor Oil


One of the best products on the market is Castrol's 06470 GTX synthetic motor oil which is, in fact, a blend of oil with powerful additives. This mix allows the oil to fully and adequately lubricate the engine and its moving parts maintain the seals and reduce the leaks. And, of course, protect it from build-ups of sludge. It is a recommended and highly-graded product.

Castrol 06470 GTX High Mileage 20W-50 Synthetic Blend Motor Oil, 1 Quart, 6 Pack

Amsoil Extended Life Synthetic Motor Oil

It is a slightly more expensive option but well worth the price since Amsoil has not only a special new formula for older engines but also contains additives that resist the build-up of sludge and similar deposits. This way Amsoil is not only preserving your old engine but it keeps it clean for longer.

Amsoil XL 5W-30 Synthetic Motor Oil