Can I use Diesel Oil In Gas Engine? Know It Now

Diesel oils generally have better additives than gas engine oils despite having similar viscosities. Diesel oil uses additives such as zinc and phosphorus, which offer excellent lubrication, specifically for old camshaft motors.

Although if you use diesel oil in a gas engine, you will face some problems. For example, if you use diesel oil, you may need to replace the cat converter more quickly than expected. You can use diesel oil if it meets your engine’s viscosity and specification requirements.

Diesel oil may not offer the same protection as gas engine oil. Ergo, if you put diesel oil into your gasoline engine oil, you can continue it if the grades match. To know more, please stay with us.

diesel oil in gas engine

What Is Diesel Oil?

Diesel oils are formulated to perform with diesel engines. Even it comes with different properties than other engine oils. The quality of lubricating oil can make it thinner. Besides this, it’s necessary to use diesel engines at high speeds. This oil type has extra additives that can prevent oxidation, corrosion, and foaming.

You need to lubricate your diesel engine to prevent premature wear and tear of moving machine parts. To acquire this, you must add it to your engine to reduce replacement costs.

What Is Gasoline Engine Oil?

Gasoline engine oil meaning is that this is the fuel used to run motor vehicles. Generally, in modern usage, the gas engine refers to a heavy-duty industrial engine. This engine can run continuously with full load for a high fraction of 8,760 hours per year.

All engine oils come with a mixture of base oil and additives mainly used in mechanical engines. In addition, it can decrease the wear and tear of machines. Each oil is mixed to meet the lubricant performance required by the applicable legislation standards. Therefore, this engine oil is suitable to use in large combustion engines.

What’s the Key Difference Between Diesel and Gas Engine Oil?

However, the difference between diesel and gas engine oil is not a big deal. Diesel formulations contain fewer friction modifiers, making them less slippery. As you know, it has ZDDP and extra detergent than gas engine oil. Here below, we give some differences between them:

Read more about Diesel Engine Oil vs. gasoline Engine Oil

The Viscosity

When thinking about engine oil, viscosity immediately comes to mind. The reason is that it’s an essential lubricant component. Therefore, getting the proper thickness is very important. The selected consistency must be pumpable at the lowest temperature.

Generally, diesel engine oil is a higher viscosity oil. Various problems can arise if we put this high viscosity in a gasoline engine. The first one is heat production from the internal liquid traction. A second problem is the high viscosity and low-temperature pump ability. During a cold start, the oil is too thick.

It can be difficult for the oil pump to deliver to the engine’s vital elements in the lifter valley. Indeed, it will inevitably lead to premature wear because the ingredients will contact each other without the lubrication advantages.

The Additive Levels

Additives are another essential component of engine oils. Nevertheless, both engine oils contain different volume levels and elements. Diesel oil has extra additives to create the oil to withstand the engine’s high pressure.

But when you add this additive to gasoline oil, it can lower the performance of your car. Furthermore, they can lose your engine’s efficiency and compression.

The most common over-based detergent additive has several functions, but the major ones are acid neutralization and cleaning. Diesel engines make many soot and combustion byproducts.

So how can I know if the oils are for gas or diesel engines? Look for the API donut when you read a label. Thus, this donut will have a service designation on the top. This designation will begin with an “S” for gasoline engines or a “C” for diesel engines.

The Replacement Intervals

Different engine oils are available in the market, each with a different lifespan. Diesel oil has more additives that last longer and needs fewer oil changes.

The Catalytic Converter & Emissions

A catalytic converter is an element of the exhaust system. Consequently, it includes perforated metal fillers and is located between the muffler and the engine. Hence, its function is to convert dangerous engine emissions into stable byproducts before entering the atmosphere.

Adequately, diesel oils contain higher anti-wear (AW) loads in the form of zinc dialkyl dithiophosphate. In diesel systems, catalytic converters deal with this problem, while gasoline systems do not. Remarkably, it’s one of the primary reasons you don’t want to use diesel in your gasoline engine.

What Happens If I Put Diesel Oil in a Gas Engine?

Some things will likely occur if diesel fuel enters your gas engine’s fuel system. So, let’s see precisely what appears and creates the problem if it happens to you.

Fuel Pump Issues

Diesel oil can’t handle the gasoline fuel pump because it’s too thick. Fuel pumps struggle to remove extra viscous mixture through the car’s fuel systems. It can create an enormous strain and possibly a significant fuel pump failure.

Clogged Fuel Filter

Because diesel is thicker, it won’t pass through quickly as your fuel systems filter gasoline. Oily diesel fuel can instantly clog the fuel filter and cause your system to fight.

Clogged Fuel Injectors

Any diesel oil can clog your car’s fuel injectors. Usually, if you use diesel oil, it can cause your vehicle to become inoperable and shut down.

You may travel a bit as your car burns through gasoline in the field system. Before the diesel injectors clog, you need to call a tow truck.

What Could I Do If I Accidentally Put Diesel Oil In My Car?

If you accidentally put diesel in your vehicle, you may think about what you need to fix the situation. Here’s how you need to react when you catch a mistake.

Don’t Start the Car

Before starting the car, it’s best to catch the mistake. Subsequently, if you can see the error, you can limit the damage to the fuel pump and fuel injectors.

Generally speaking, if you can’t catch the fault after starting the car, stop it as soon as possible. For parking your vehicle, you should find a safe area. Also, you need to call someone to provide you with a ride.

Call a Tow Truck

Continuous driving or running the engine will worsen the problem. Call a tow truck immediately and get a tow. This will reduce the amount of damage. Similarly, it also can give you the chance to reduce your repair bills. Likewise, if your car has an insurance policy, you can call them, and they can help you.

If your car insurance policy includes emergency roadside assistance, you may want to give them a call and contact an authorized tow truck company. Depending on where you need to have your vehicle towed, you may not have to pay anything to have your car towed.

Get To a Mechanic

If your car gets damaged, you want to go to a mechanic. It’s because most people make this mistake. That’s why you have to go to the mechanic and solving your problem is the best idea. However, it will probably cost more than you expect.

So When Should I Use Diesel Oil in My Gas Engine?

When you need to use diesel oil in a gas engine, here are some situations:

  • You may need diesel to ensure your machine is adequately protected when you use low-quality oil.
  • Also, if you use a high-performance engine, you may need diesel to maintain it.
  • If you use an older machine, you need this oil to help its engine run properly.
  • Generally, you need to use diesel oil if you live in winter weather.
  • Because of the use of off road-vehicle, they may need diesel to help your engine against dirt and debris.

Well, you may need diesel oil on your gas engine in all these situations.

will diesel engine oil damage a petrol engine

Can I Safely Use Diesel Oil in a Gas Engine?

It carries diesel oil and relies on original equipment manufacturer (OEM) recommendations. The (API) publishes the diesel oil “C” category and the “S” category for gas engine oil.

Though you can sometimes use this oil on a gas engine, it’s not recommended. And also, this diesel oil comes for diesel applications. But drivers who want to use it can use a gas engine otherwise. Only you can use the manufacturer’s recommended oil. Accordingly, diesel oil uses a very different formula and is incompatible with gas engines.

The problem lies with the control properties of diesel oil, which is generally heavier than gas engine oil. For example, a regular old diesel vehicle uses 15w-40 oil, while some modern gas vehicles use 5w-20 oil. In this case,

Some people want to use 15W-40 diesel oil in gas engines. In particular, this oil is often easier to find. Sometimes, finding a similar viscosity of diesel oil for gas engines is very tough. Others favor the enlarged emergency of diesel oil.


Q. Will Diesel Oil Hurt a Petrol Engine?

Accordingly, diesel oil can’t hurt your petrol engines if you use it. In other words, if diesel oil meets the correct specifications and requirements, it does not cause engine damage. Generally speaking, if your petrol engine meets the specification of API SN, you can use API SN specifications for diesel oil.

Most car owners accidentally or knowingly use diesel in their petrol engines. When buying engine oil, the manufacturer suggests checking the owner’s manual if you’re unsure. Instead of harming your engine, it can help to clean dirt and grease.

Q. Can You Use 15W40 Diesel Oil in Gas Engine?

You can use 15W40 diesel oil in a gas engine because it contains high viscosity. Most importantly, this oil can meet your machine’s viscosity requirements and other specifications.

For instance, you can use diesel oil when your gas engine needs 5W30 oil with the correct API SN specification. The reason is that it can meet similar viscosity and API SP requirements. On the other hand, you can’t use diesel oil in a regular engine.

Undoubtedly, you can use 5w30 because it provides incredible value and performance. The owners of gas engine cars like to use diesel over gas.

Q. Can You Put 10w30 Diesel Oil In A Gas Engine?

If your diesel oil meets the proper specifications and viscosity, you can use 10w30 diesel oil in a gas engine. Alternatively, for regular gasoline applications, diesel oil isn’t necessary. The correct choice is a quality gas oil for both value and performance.

Q. Can you use Rotella Diesel Oil In a Gas Engine?

In a nutshell, you can’t use Rotella 15w40 diesel oil in a gas engine. But if you accidentally use it, you can figure it out. Yet, you may experience problems like vehicle shaking while riding. This eventually can damage your engine!

Hence, if you use this Rotella 15w40 with a gas engine, your car will experience many problems. First, the car is most likely to start correctly. Even if it does, it will automatically turn off after a while.

Also, your car may shake if you drive it too hard. Gradually, the car’s engine will deteriorate, leading to damage. Also, you may face an accident because of the disruption of the machine.

Rotella is not suitable for gas engines for several reasons. First, diesel fuel has a denser and denser viscosity than gas. As a result, the diesel mixture will have difficulty moving through the fuel pump system.

Additionally, diesel fuel will not pass through the filter as easily. Regardless, this will clog the fuel filter instead. And any diesel entering the engine can block the fuel injectors. And this will eventually render them ineffective.

Final Thoughts

Remember that not all diesel oils are compatible with gas engines. Diesel motor oil has a dangerous additive, and it isn’t present in gas oil. That’s why, if you use diesel oil, it can usually damage your catalytic converter.

Above all, some diesel manufacturers include it on the label to use it with good grade in gas engines. After knowing the possibility of using diesel oil in gas engines, engine protection must be kept in mind.

Unfortunately, taking your vehicle to the mechanic is a good idea if you notice any issues or trouble. Ultimately, this article discusses whether can I use diesel oil in gas engines. We hope you may now know what the truth is.


I am Engr. Z Eusuf Lubricant Specialist, Mechanical Engineer & has been working with engine lubricants for a long time and knows what makes them work best. I can help you find the right oil for your needs, and I have tips on how to keep your engine running at its best.