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Car Accessories, Car Maintenance, Cars & Automotive

7 Best Oil Additives for Cars Reviewed in 2020 (UK & US)

What is the best oil additive? At Only Reviews, our team have tested and reviewed the market's best oil additives below

Last updated on 10th Jan 2020 by Rachel

Quick Comparison

We interviewed 7 Petroleum Engineers, visited 3 Oil Refineries, spoke to 5 Car Mechanics and read innumerable online reviews to prepare an initial list of 20 oil additives.

Then, we compared the performance of each of these additives against various indicators including lubrication, protection against wear and tear, performance against dry sludge build-ups, and ability to bring down the temperature.

As a result, we were able to narrow down our list to the 7 best oil additives on the market, of which the Slick 50 Engine Treatment Oil Additive gets our nod to be the best.

It provides enough lubrication to not only remove dry particles’ build-ups but also decrease temperature and reduce wear and tear.

Also, it comes with a respectable warranty.

  1. 1
    100%
    100%

    Liqui Moly 1580 Racing Bike Oil Additive 125 ml

    Liqui Moly 1580 Oil Additive prevents engine wear using a formulated MoS2 (molybdenum disulfide) agent. It is certified to reduce engine wear up to 50%.

    This high-grade bike oil additive helps the engine to run smoother while maintaining a good oil economy as well as high horsepower.

    It ensures fewer breakdown, engine quietness and optimal performance for years.

    It is recommended to use this oil treatment during each oil change for 2-cycle engine every time you fill up.

    It is also recommended to use with different wet plate clutch.

     

    The Good
    • Reduce engine wear
    • Enhance oil economy
    • Fewer breakdowns
    The Bad
    • Only used for motorcycles
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  2. 2
    100%
    100%

    Slick 50 Engine Treatment Oil Additive Review

    Slick 50 Engine Treatment Oil Additive provides a smooth flow of engine components in most stressed situations, such as carrying heavy loads, towing, or in heavy terrific.

    It is a unique chemical oil additive package that ensures lower wear surface and friction.

    The anti-wear agents used in its formula creates a regenerating layer of the protective surface between the engine parts to prevent rating together.

    An efficient dispersant in the Slick’s formula helps to prevent the build-up of dry residues and sludge on the engine parts.

    It is suitable for both diesel and petrol engines.

     

    The Good
    • Suitable for both diesel and petrol engines
    • Anti-wear agents
    The Bad
    • Few seal broken complaints
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  3. 3
    100%
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    BestLine Engine Treatment, 16 oz / 473 ml Review

    The BestLine Engine Treatment oil additive is compatible with all kind of oils. BestLine Oil products have always promised high-grade quality engine oil treatment.

    This oil additive wraps the engine parts with an essential lubricant that resists wear and friction.

    It cleanses, clear, and protects all parts of the engine parts with a regretting protective lubricant layer – reduces harmful emission.

    BestLine Oil Additive ensures great efficiency and optimal performance for years.

    It is recommended to add 10-15 percent oil additive by the total volume of engine oil. It can be used for motorcycles, cars, as well as boat engines.

     

    The Good
    • Resist wear and friction
    • Can be used for boat engines
    The Bad
    • Expensive than other oil additives
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  4. 4
    94%
    94%

    Royal Purple 01600 Purple Ice Radiator Additive

    Royal Purple 01600 is a high-grade synthetic coolant radiator additive for both diesel and gasoline engines.

    It is specially manufactured and formulated with efficient additives to reduce the coolant’s surface tension, which enhances the heat transfer throughout the cooling system.

    Besides maintaining the heat transfer, it also protects the engine components against corrosion, rust, and erosion.

    It features a wetting agent and corrosion inhibitor to provide effective protection to aluminium covers and to sooth the hot spots in the cylinder heads and engine to prevent basic engine failures.

    The Good
    • Enhance cooling system
    • Prevents corrosion, rust, and erosion
    The Bad
    • Few seal broken complaints
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  5. 5
    90%
    90%

    Archoil AR2820 Professional Engine Flush 250ml

    Archoil AR2820 is one of the best engine additive oil that helps to remove deposits from both diesel or petrol engines and enhances their lubrication systems.

    It features excellent carrier fluid and latest dispersants to remove gum, sludge, particulates, and enhancing engine optimal performance and compression lost through excessive sludge and deposits build-up.

    These deposits are often suspended in the old lubricating oil and then disposed of with the use of this amazing oil treatment.

    When using AR2820, the new oil will definitely last longer and the cleaner surfaces will effectively enhance the engine performance.

     

    The Good
    • Professional engine flush
    • Clean the inner surfaces
    The Bad
    • Thick for some filters
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  6. 6
    84%
    84%

    Castrol 19589812 1L Racing A747 Oil Review

    The Castrol Racing Oil Treatment Solution is a fully synthetic engine oil additive for all types of two-stroke engines.

    It is manufactured using a highly formulated agents and castor oil that provides efficient lubrication as well as reduce wear even under extreme stress conditions.

    The special detergents additives utilized in Castrol Racing Oil Additive provide excellent cleanness at the pistons, combustion chamber, and spark plugs.

    The fully synthetic castor oil racing technology ensures no dry residue in the cylinders while keeping the engine thermally stable for high-temperature conditions

     

    The Good
    • Castor oil racing technology
    • Efficient lubrication
    The Bad
    • Only used for 2-stroke engines
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  7. 7
    84%
    84%

    Lucas Oil 10001 Heavy Duty Oil Stabiliser, 946 ml

    Lucas Heavy Duty Oil Stabilizer is a 100% petroleum product manufactured under high-grade conditions through enormous field and laboratory testing.

    This excellent engine oil additive is capable of fulfilling all lubricating needs of both diesel and petrol engines.

    It helps to eliminate dry residues and prevent engine’s thermal breakdowns.

    It also eliminates the engine knocking, reduces oil consumption, and stops smoking of old worn engines while extending the oil life span up to 50%.

     

    The Good
    • Can be used with all petroleum products
    • Adds excellent lubricity to engines
    • Consistent results
    • Non-toxic chemicals
    The Bad
    • May not improve mileage
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Side-by-side

100%

Liqui Moly 1580 Racing Bike Oil Additive 125 ml

  • Reduce engine wear
  • Enhance oil economy
  • Fewer breakdowns
Check price on amazon
100%

Slick 50 Engine Treatment Oil Additive Review

  • Suitable for both diesel and petrol engines
  • Anti-wear agents
Check price on amazon
100%

BestLine Engine Treatment, 16 oz / 473 ml Review

  • Resist wear and friction
  • Can be used for boat engines
Check price on amazon
94%

Royal Purple 01600 Purple Ice Radiator Additive

  • Enhance cooling system
  • Prevents corrosion, rust, and erosion
Check price on amazon
90%

Archoil AR2820 Professional Engine Flush 250ml

  • Professional engine flush
  • Clean the inner surfaces
Check price on amazon
84%

Castrol 19589812 1L Racing A747 Oil Review

  • Castor oil racing technology
  • Efficient lubrication
Check price on amazon
84%

Lucas Oil 10001 Heavy Duty Oil Stabiliser, 946 ml

  • Can be used with all petroleum products
  • Adds excellent lubricity to engines
  • Consistent results
  • Non-toxic chemicals
Check price on amazon

Frequently asked questions

What does it mean by adding Oil Additives?

The oil we often used for engines isn’t just a solution of raw petroleum pumped out from the ground.

It is a mixture of refined oil-based residues as well as a package of various additive components that are blended in such a way to make engines work properly.

Adding oil additives to engines ensure a frictionless journey to the engine, increase horsepower, reduce engine wear, and restore fuel economy.

In simple words, oil additives not only lubricates working to reduce friction but also protects it from corrosion and rust.

 

What are the advantages and disadvantages of adding Oil Additives?

Engine oil additives ensure a prolonged engine life as well as serve a moderate fuel economy.

One big advantage of utilizing oil additives is that they can be used with both synthetic and mineral engine oils.

They improve the engine’s performance, reduce friction, extend the lifespan of engine oil as well as the engine, and prevent sludge.

However, they surely add up the expensive over engine oils.

Also, the excess use of additive oils can let the highly concentrated anti-flaming agents worsen the condition

What things to consider when selecting the best engine oil additives?

There are certain things one must consider before selecting the best engine oil additive.

While engine oil additives improve fuel efficiency, increase horsepower, keep engine smooth at efficient RPMs, eliminate dry residues, reduce emissions and much more, their functioning may vary from engine to engine.

For instance, some oil additives are not recommended for motorcycles while some are only used for motorcycles.

Keeping this in mind, consult your automotive mechanic for the best recommendation as well as follow the review list of the best oil additives below.

What is the approximate price range for different Oil Additives?

The price range for different oil additives vary.

For instance, you will not find the motorcycle oil, diesel additive, and synthetic motor oil at the same price.

However, you can find the best oil additive for you in the price range of £10-£20.

Which is the best Engine Oil Additive? Why is it the best?

Slick 50 Engine Treatment Oil Additive efficiently provides a smooth journey against friction and dry residues.

The excellent anti-wear components in Slick 50 Engine treatment creates a self-regenerating surface between the metal parts to prevent the grating and tear.

Learn more about the Slick 50 Engine Treatment in the review below.

What is synthetic motor oil?

Synthetic motor oils feature purer and highly refined base oils than that of conventional mineral oils.

They offer great performance and superior protection far better than traditional motor oils.

They offer a number of benefits for engines to maintain the optimal performance for years.

Which is the best synthetic motor oil additive? Why is it the best?

BestLine Engine Treatment, 16 oz / 473 mlis the best synthetic motor oil additive. It is designed to protect and clean the internal components of the engine.

It prevents wear and resists friction while keeping the engine in optimal performance for years.

Follow the review list to learn more about the BestLine Engine Treatment

Which is the best royal purple oil additive? Why is it the best?

Royal Purple 01600 Purple Ice Super-Coolant Radiator Additiveis the best royal purple oil that increases the engine efficiency as well as lifespan. This amazing 2-in-1 corrosion inhibitor and wetting agent creates a new layer for better projection of the internal surface of the engine. Follow the review list and learn more about the Royal Purple 016000 Oil Additive.

Which is the best motorcycle oil additive? Why is it the best?

Liqui Moly 1580 Racing Bike Oil Additive 125 mlis the best oil additive for motorcycles.

It provides great engine protection, reduces friction, and lower wear for up to 50%.