7 Of The Best Oil Additives For Older Engines

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An older vehicle engine can require a bit more time and elbow grease. A beneficial option to keep your engine running at top performance is oil additives. If your car has made it this far, why not keep it running for longer? We’ve gone deep into oil additives and researched which will work best for older engines. 

Even with so many brands for additives, most offer the same general benefits. Antioxidants reduce the inflow of oxygen to help slow corrosion and layers the engine surface to lessen friction. Furthermore, lower emissions are given off while it adds longevity to your oil base. Finally, many additives can aid in sealing small cracks or scratches in seals and head gaskets. Below, you’ll find the best oil additives for older engines:

  1. STP Oil Treatment
  2. Prolong Super Lubricants Engine Treatment
  3. Marvel Mystery Oil
  4. Lucas Heavy Duty Oil Stabilizer
  5. Liqui Moly Cera Tec Friction Modifier
  6. Restore Engine Restorer + Lubricant
  7. Seafoam High Mileage Motor Treatment

As stated above, the number of brands can be overwhelming. We’ve put together a list of the best seven oil additives for older engines. Let’s not forget too which ones will work with your type of oil and fuel. These engine supplements are meant to be a helping hand and should be used in combination with your normal oil. Let’s take a drive and learn about how to keep your old engine alive and well.

Oil change in car service. Hand in protective glove with oil bottle, 7 Of The Best Oil Additives For Older Engines

7 Of The Best Oil Additives 

1. STP Oil Treatment

Owned by Energizer, STP has been around since the 1950s. This oil treatment can be used with both conventional and synthetic oil. It is best to add STP Oil Treatment to new, warm oil. Containing zinc reduces oil burning while lubricating all moving parts of the engine. The full coverage will aid in keeping your engine cool as it reduces the heat produced by friction. An additional feature of this brand is that it offers an overall oil for all engines and one specifically for 4-cylinder vehicles. 

Click here to view STP Oil Treatment on Amazon.

2. Prolong Super Lubricants Engine Treatment

Designed for both gasoline and diesel engines, Prolong has been in business since the 1990s. While this oil treatment does not contain zinc, it has other chemicals that adhere to the engine’s metal surface. Since it adheres so well, your engine is already lubed before the engine oil starts to enter the pistons. Prolong’s brand is well known for performing efficiently under intense pressure conditions.

Click here to view Prolongs Engine Treatment on Amazon.

3. Marvel Mystery Oil

Available for gasoline, biodiesel, diesel, and conventional or synthetic, Marvel can do it all. The company started in 1923 and has since prided itself on giving your engine more power. A key feature is that their oil forms a tight top ring seal, thus allowing less leakage throughout the engine. With fewer leaks comes higher compression and increased power. Marvel is a good pick for engines that are in the cold weather or not driven every day.

Click here to view Marvel Mystery Oil on Amazon.

4. Lucas Heavy Duty Oil Stabilizer

Not only can Lucas be added to your engine oil, but also to your gear oil. Made from pure petroleum, their products have multiple uses. When mixed in with the oil, this stabilizer can minimize engine noises and lubricate transmission to keep the heat down. The Lucas brand is heavily involved with the American Truck Stop Industry.

Click here to view Lucas Heavy Duty Oil on Amazon.

5. Liqui Moly Cera Tech Friction Modifier

A trusted name brand, Liqui Moly has been produced in Germany for over 60 years. The Cera Tech modifier is comprised of lubricant and chemical enhancers within a batch of strained petroleum, also known as mineral oil. It is best to add Liqui Moly to fresh oil that can be either cold or warm. Mineral oil is typically safe to use with all standard motor oils and filters. However, always check your manual to make sure.

Click here to view Liqui Moly Modifier on Amazon.

6. Restore Engine Restorer + Lubricant

As vehicles climb over 100k miles, internal components are going to be showing their wear and tear. Restores lubricant is manufactured with CSL; a lubricant specifically made for severe pressure conditions. CSL works to give you a smoother ride by evening out the engine’s cylinder pressure while producing better horsepower. It is aptly named Restorer because it helps seal cracks to restore your combustion chamber. 

Click here to view Restore Engine Restorer on Amazon.

7. Seafoam Motor Treatment

Another known name, Seafoam, has been in the automotive game since the 1930s. Built off the desire to play more and work less on keeping an engine clean, Seafoam works to keep your engine sludge-free. In particular, this motor treatment runs throughout the injectors, carb jets, and intake valve to break down unwanted build-up. Recommended to use every 3k-5k miles, the instructions will tell you how much to add based on what you’re looking for. Seafoam is able to be used in gas or diesel ad convention or synthetic. 

Click here to view Seaform Motor Treatment on Amazon.

Should you put thicker oil in an older engine?

A hotly debated question. If you live in a warm climate, then thicker oil can be a good choice since it won’t have time to clump up. Thicker oil requires more energy to cycle it through the engine, so if you don’t drive your older car every day, a thinner oil would be better for you. An exception can be if you keep your car in good condition and are planning a long and hot trip, then thick oil will help cover your pistols better. 

Thin oil will fair better in colder weather where it won’t have as much body to chill. It will also be easier for your engine to warm it thoroughly. When you perform oil changes or if you take your car to a shop, ask them to keep an eye on the consistency of the oil. Sludge-filled oil changes will be an indicator that your oil is too thick.

How often should you change your oil in older cars?

The frequency of oil changes could depend on your driving environment. But, the trusted rule of thumb is every 3,000 miles or three months, whichever comes first. Older car’s engine oil should be checked every few thousand miles to know how fast the color is changing. By monitoring the oil dipstick, you’ll be able to track your vehicle’s specific needs. You will want the oil to be a clear amber color. If the oil starts to get dark and thick, it’s time to change the oil.

Car mechanic checking oil level

Differences between older and modern car engines

While cars still get you from point A to point B, there have been some major changes in the engine. Older models, in decent condition, are known to burn more oil and can be made from steel, thus making the body heavier. Newer engines are much smaller now due to the transition to computer components verse mechanical parts. While that might make them more powerful and fuel-efficient, a trained technician is needed when something breaks on a newer engine. 

With this in mind, older engines can still be just as reliable with proper maintenance. The engine’s mechanical parts tend to be more straightforward when they need to be fixed and won’t cost an arm and leg if taken care of right away. Another thing to think about is that since the engine space is so much more compact, you’ll get more room inside the vehicle. 

In Closing

There’s a saying that they don’t make ’em like they used to, and there’s some truth to that. For those classic car owners that just can’t let go, an oil additive could be just the boost your engine needs. Oil additives strengthen the oil that’s already there and protect your engine from further wear and tear. Infused with lubricants, additives work to coat gaskets and pistons to reduce friction and build up. Regular maintenance of your vehicle’s engine will make sure it runs like the way it was designed to.

Looking for more vehicle maintenance? Check out these articles:

How Long Does It Take To Replace An Engine?

10 Top Motor Oil Brands – How To Choose Yours

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