What Kind of Oil Does a Generator Use?

What Kind of Oil Does a Generator Use

Most generators use engine oil for their functioning and maintenance. There is a wide variety of oils in the market that are useful for generators.

Generally, the generators use SAE 10W-30 engine oil, this oil can be used in cold weather but using it in hot weather is recommended. SAE 10W-30 engine oil is explicitly composed of all the ingredients that are useful for smooth and flawless operation. You can also use its synthetic variation 5W-30.

Generator fuels and oils are the most basic requirement of a generator. Many companies in the market have introduced their range of generator oils and fuels. There is a wide range of generator oils. Choosing the right oil for your generator is very important. If you are confused by the variety of oils in the market and unable to select the best one, we can help you with this problem.

Read the article till the end to ease your way through this purchase. We will guide you to get the best oil for your generator.

BUY ON AMAZON: SAE 10W-30 engine oil

BUY ON AMAZON: 5W-30 Synthetic Variation

Table of Contents

Importance of engine oil

What Kind of Oil Does a Generator Use

Engine lubricant is necessary for the generators. The engines in the generator produce a lot of friction among the parts of the generator. The essential parts of the generator might get jammed or blocked, affecting the functioning of the generator. Good-quality engine oil provides the following advantages to the engine.


The large parts of the engine work together to give proper functioning. The internal parts produce a lot of friction which in turn produces heat. As the speed of the engine increases, more and more friction is created, which generates enough heat to destroy the entire engine.

Engine oil provides lubrication to these parts of the engine and prevents them from overheating and frictional damages. It covers the internal metal surfaces with the help of oil films. It reduces friction between the large parts of the machine.


Although some proper cooling systems and mechanisms help in the better operation of the generator, the engine oil helps in the dissipation of heat from the generator set. As the oil flows through the engine, it takes the heat generated by friction away from the system.

Some parts of the generator, such as the piston, are away from the cooling systems. These parts can take cooling effects with the help of this oil.

Rust and corrosion-free functioning

When the engine is running for an extended period, the oil in some of its parts produces oxides which might cause corrosion. The strong acid in the corrosive substances might cause erosion to the internal engine. It might burn the moisture as well. To prevent these damages, there are special additives in the oil that prevent the engine from rust, corrosion, or any other damage to the generator caused by the harmful substances.

Cleaning and maintenance

When the generator is operating for a long time, carbon is generated. Many residues are also present in the engine, which attach to the internal parts of the engine. The function of the generator engine is badly affected by the mistreatment of these residues.

The piston rings and some valves are affected, and they cause detonation, extra fuel consumption, and frustration to the generator’s engine. The engine oil has a clean dispersion function, which does not accumulate residues in the generator.


Usually, a piston ring is present between the piston and the cylinder wall. It provides sealing to the engine. But the metal surface is not very flat, so the sealing degree is not very satisfactory. If the sealing effect is not good, the power of the diesel engine is reduced. By using engine oil, the oil produces a film between the metal. This provides an excellent sealing effect. Moreover, the efficiency of the generator is also improved.

Generator Fuel – The Essential Requirement of Generator

The engine oil in the diesel engine of the generators has many essential functions. Some of the generators in the market use the same oil as used by cars. But most of the time, this type of oil is costly. But there are also some cheaper options for the oils. These oils also give better performances.

Different generators can be run on different types of fuels. Some of the generators run on a kind of fuel are explained as follows.


Gasoline generators are the best option for people who use generators as a backup for power breakouts. Gas generators have the great advantage of being less expensive than other generators. Gasoline has a low shelf life, and its blending absorbs most of the moisture within a month. Many years old gasoline is also equally viable, but it can cause some damage to the internal parts of the engine.

One of the significant disadvantages of a gasoline generator is that it needs to be refuelled regularly. The refuelling of the generator does not depend upon weather or any other outer condition. In case of any natural disaster or power outages, it might be not easy to find gasoline. These generators need more care, and gasoline is more dangerous to store than other fuels.


Diesel generators are a good option for users that need to run generators regularly. These generators are much more advantageous than others. Diesel is also safer to store than gasoline. It is more efficient and very low-maintenance. Moreover, diesel generators give more horsepower per gallon than gas generators. Also, they have a longer shelf-life.

However, there are some things about diesel that the user might not like to have in the ideal generator oil. Diesel is usually more expensive than gasoline. Diesel generators are specially made for regular use. If you do not run the generator daily, the generator might get more prone to breaking down.


Propane generators are more popular for recreational uses like picnic, camping, RV, or other outdoor activities. These generators use propane as a fuel which is also known as liquid petroleum gas. One of the significant plus-point of propane over different fuels is that propane does not degrade during storage periods. It is, therefore, a more viable option than other types of fuels.

Propane requires a separate storage tank other than the generator. You can either keep a small-sized tank like that of heater and grill or a large-sized tank that is refilled by the service truck. Propane has the disadvantage that it is less efficient than both gasoline and diesel. It usually offers less power.

Natural gas

Natural gas is considered the best fuel to be used by a generator. The advantage of using natural gas as a fuel for your generator is that it does not require refilling, and it costs much less than any other fuel. They can be cleaned and maintained very easily. They are more efficient and environment-friendly.


We have gone to the last mile to provide you with the best information regarding the engine oil used by the generators. The types of fuels, their pros and cons, and the importance of using the right fuel in your generator engine are explained well. It will help you get the best fuel filled in the generator. We hope that this article has helped you gain all the helpful knowledge about fuels.

Generatorrookie.com uses affiliate links (No Additional Cost For You). As an Amazon Associate, I earn when you purchase Using My Affiliate Link. Learn more.


Hi, Welcome to Generatorrookie.com; My name is Shahzad, and I know about generators because I grew up in a country where power outage is very common. I share Tips, How-To, News, and Reviews for the best generators or anything related to generators.

Recent Posts