Everything you need to know about additives in your motor oil
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How do Additives in Motor Oil Work
Why are Motor Oil additives important
Base oil and additives are the two main parts that make up motor oil today. It wasn’t always like that, though. In the 1930s, someone came up with the idea of adding wax modifiers to base oil to get rid of the wax left over after refining. So, people started adding things to motor oil to make the base oil work better.
In this post, we’ll talk about the chemicals that are added to motor oil. These additives make the lubricant better by doing two important things: they stop things from breaking down and they make the good things about the base oil even better.
If you’re interested in aftermarket oil additives (which you add to your motor oil) and whether they work, check out the post below.
Additives to motor oil: what they do
Additives in motor oil are important for three main reasons:
- Protect metal surfaces
- Add more ways to use the lubricant.
- Extend lubricant life
Other things to think about when choosing an additive are how easy it is for formulators to work with it, how stable it is in storage, how toxic it is, and how it smells. Yes, even the smell of an additive is something to think about.
Additives that protect surfaces
Five kinds of surface problems are fixed by the additives in motor oil for cars.
Anti-wear agents cut down on friction and wear, and they also help keep things from scoring or getting stuck. They help keep metals from touching each other through chemical processes. Some anti-wear agents are…
- Phosphates
- Organic sulfur and chlorine compounds
- Sulfurized fats
- Sulfides
- Disulfides
Corrosion and rust inhibitors help keep engine parts from rusting and corroding. Among them are…
- Zinc dithiophosphates (ZDDP)
- Metal phenolates
- Fatty acids
- Amines
Detergents get rid of varnish and sludge by making them less acidic. This keeps surfaces clean and free of deposits. Among them are…
- Metallo-organic compounds of sodium, calcium and magnesium phenolates
- Phosphonates
- Sulfanates
Dispersants help keep contaminants that don’t dissolve in the lubricant from sticking together. Polar attraction binds the contaminants to the molecules of the dispersant, which keeps them from sticking together. Among them are…
- Alkylsuccinimides
- Alkylsuccinic esters
- Mannich reaction products
Friction modifiers help cut down on friction and use the least amount of fuel possible. Some things that change friction are…
- Organic fatty acids and amides
- High-molecular-weight organic phosphorus
- Phosphoric acid esters
What are Performance additives in motor oil
Additives in motor oil are also used to make the oil flow better in cold weather, protect seals, and make it more stable in terms of viscosity.
Pour-point depressants change the way wax forms so that lubricants can flow at lower temperatures and provide better wear protection at the start of an engine. Among them are…
- Alkylated napthalene and phenolic polymers
- Polymethacrylates
- Copolymer esters
Seal-swelling agents help elastomeric seals get bigger so that they don’t leak. Among them are…
- Organic phosphates
- Aromatic hydrocarbons
Viscosity modifiers slow down the rate at which a substance’s viscosity changes when the temperature goes up or down. This makes the lubricant work better across a wider range of temperatures.
- When the temperature goes up, polymers and copolymers of olefins tend to get bigger, which stops the oil from getting thinner.
- Methacrylates, dienes, and alkylated styrenes are also used to change the viscosity.
How do Protective additives help motor oil
There are also “protective” additives in motor oil that make the lubricant’s protective properties even better.
When engine parts or gears move, air can get into the oil and make foam. If foam bubbles break, metal parts can touch and wear out faster.
Anti-foamants lower the surface tension of foam bubbles, which makes them pop more quickly. Without defoamers, when a customer came in for an oil change, foam would gush out of the dipstick tube. Some common anti-foaming agents are…
- Silicone polymers
- Organic copolymers
Even though we need oxygen to live, too much of it can make lubricants less effective. Oxidation speeds up how quickly a lubricant breaks down and stops working. Antioxidants break down peroxides and stop free-radical reactions. This slows oxidation and lengthens the life of lubricants. Some examples of antioxidants are…
- Zinc dithiophosphates
- Hindered phenols
- Aromatic amines
- Sulfurized phenols
Formulators also use metal deactivators, which stop metals from speeding up the rate of oxidation, to slow it down. These chemicals form a film on metal surfaces that doesn’t do anything. They are…
- Organic complexes containing nitrogen or sulfur
- Amines
- Sulfides
- Phosphites
why is Motor oil is a complex system
As can be seen, the additives in motor oil are part of a complex system in which each component is harmoniously tuned to provide the best possible protection for your engine. When formulating motor oil, chemists carefully consider how different base oils and additives will interact and function within the engine or lubricated system. A miscalculation can reduce the effectiveness of the oil.
The conflict between corrosion inhibitors and anti-wear additives is one example. Occasionally, these additives compete for surface sites on metals. Using an excessive amount of corrosion inhibitor can reduce the anti-wear properties of the oil.
- Using additives in motor oil improperly can result in disadvantages. Here are some examples of the potential adverse effects additives may have.
- In high-temperature regions, detergents and anti-wear additives can promote deposit formation.
- Detergents and dispersants can reduce the efficacy of anti-foam additives and increase foam formation.
- When subjected to high temperatures, some additives can cause corrosion.
- An excessive amount of anti-foaming agent will result in foam.
What it means for you
Motor oil and other lubricants are delicately balanced, chemically sensitive systems. Follow these guidelines for the best protection and longest lubricant lifespan:
Avoid mixing lubricants – Although nearly all conventional and synthetic motor oils are compatible, you should avoid mixing them if possible. Sure, topping off the engine with a different brand of oil won’t cause engine damage, but it’s best to always use the same oil. If you must mix lubricants, immediately drain the system and refill it.
Avoid using aftermarket oil additives – Store shelves are littered with aftermarket additives that promise to increase fuel economy, reduce wear or restore an old engine to like-new. Adding them to your oil disrupts the oil’s chemistry and may reduce its ability to protect your engine. When you’re using a good motor oil, there’s no need to modify it with an aftermarket additive.
Why AMSOIL? Superior protection against wear, improved fuel economy and better performance under extreme temperatures. AMSOIL is the only oil that is able to last up to 25,000 miles. Save yourself time and money and protect your car or truck by using AMSOIL products. Your vehicle will last longer and you will lower your maintenance expenses. Protect your Honda, Toyota, Nissan, Chevrolet, Ford, Chrysler or any other vehicle with AMSOIL synthetic oil!
We advise you to consult your owners manual for proper fluid recommendations and to consult the appropriate repair manual for proper maintenance procedures and specs. Follow all appropriate safety practices. We are not responsible for misuse of products.