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3 Best Oil Additives for Diesels (and Why Your Engine Probably Needs One)

Diesel engines provide better performance compared to gasoline engines. However, with great power, comes great responsibility. The maintenance of these engines is considerably more demanding.

Here’s what you need to know:

Despite their MPG advantage over gasoline engines, diesel engines are known to bear some unwarranted problems. Not only are they quite noisy, but they are also dirty, smelly, difficult to start in cold weather, and quite sluggish to drive.

But do they have to be all that?

The answer is a definite no. Every engine is only as good as it is treated. For this reason, the easiest and most affordable solution might be investing in the proper diesel oil additive.

Here is why:

Diesel engine oils are more than capable of protecting your engine from the elements. They can provide the much-needed servicing that your engine requires in order to avoid the issues mentioned above.

However, the active ingredients in these engine oils may be soaked into the engine components while performing the functions they were made for. As such, oil additives are best used to top up on these “ingredients”.

Best Oil Additives

Below you can find an analysis of three of the best diesel oil additives:

STP Oil Treatment Diesel

Quick Specs
  • Rating: 4.8 / 5
  • Brand: STP
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Over time, the oil additive you use in your diesel engine is bound to run low on the essential additives that make it work on your engine perfectly. These additives are lost while they perform their duties, and they require eventual replenishment. No additive can fortify your engine oil quite like STP Oil Treatment.

STP contains all the necessary additives to provide increased levels of viscosity improver, dispersant, anti-wear, and anti-friction agents. All this will increase the ability of your motor oil to protect your engine from the elements while improving performance at the same time.

It is recommended to add one bottle of STP Oil Treatment when the engine is warm.

What We Liked

  • Compatible with all engine types
  • Protects engine
  • Improves performance
  • Enhances lubrication

What We Didn’t Like

  • Has to be added every oil change for it to benefit car

No oil additive has ever been so instrumental in protecting the high-performance engines of today as well as Rev X. It completely fills the gap put in by the EPA’s mandate to remove key lubricating components from today’s diesel fuel and engine oils. This additive surpasses all specifications with amazing performance enhancements on your diesel engine. It is guaranteed to make your engine run better than new.

A great feature of this product is its ability to be blended in all types of lubricating fluids, not just your engine oil. It improves the lubricity of your engine oil making it better at avoiding the effects of friction and keeping your engine young and fresh. This, in the long run, enables your engine to last that much longer while maintaining that high level of performance.

What We Liked

  • Decreases engine noise
  • Compatible with both engine types
  • Improves cold starts

What We Didn’t Like

  • Takes some time to notice the difference
  • An extremely small amount compared to others

BestLineDiesel Engine Treatment is the most advanced diesel engine oil treatment. This treatment will clean, treat and protect all internal engine components. The engine will be coated with an ionic bonded layer of lubricant that resists friction and wears, providing efficiency and performance in one complete package.

High temperatures have an adverse effect on engine performance. There are other factors apart from normal engine operations such as friction that can play a role in increasing the operating temperatures of the engine. With BestLine Diesel Engine Treatment, you get the added benefits of friction reduction to enable your engine to operate in cool temperatures.

Another great thing about BestLine is that it is very environmentally friendly and it reduces fuel consumption, making it very economically viable.

What We Liked

  • Improves performance
  • Compatible with all motor oils
  • Reduces heat and friction
  • Reduces emissions

What We Didn’t Like

  • Not compatible with all engines
  • Expensive


All these benefits can be acquired at a fair price, and the best part is, it is quite effortless to include an additive to your fuel. No expertise is required and you can do it on your own. All you have to do is find the additive that works for you and have a go at it.

There is so much to be liked about a good fuel additive, especially one that helps you maximize your mpg while increasing fuel efficiency. Invest in one today and experience the difference.

BONUS: Watch this video of test how STP oil treatment improves engine compression rate and power.

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