Diesel oil is a type of fuel commonly used in diesel engines. It is a heavy, less refined oil used in compression-ignition diesel engines found in buses, trucks, and other equipment.
Although you can use diesel oil in a gas engine if it meets your gas engine’s specifications and viscosity requirements, it is generally not recommended.
In fact, you do not need to use diesel oil in your gas engine at all. A gas engine’s most appropriate fuel choice is quality gasoline oil for both performance and value.
What Happens if I Use Diesel Oil in Gas Engine?
Diesel oil is designed for diesel engines and can harm your car if incompatible with the gas engine fuel system.
Diesel and gas engines feature different combustion processes, and the oils for each type of engine are made to match those processes.
Using diesel oil in a gas engine can lead to reduced efficiency, decreased engine performance, and, finally, damage to the engine’s components, such as spark plugs and fuel injectors.
The oil also contains additives unsuitable for gasoline engines. These additives can clog fuel filters and injectors.
What is the Difference Between Diesel and Gasoline Engine Oil?
Diesel and gasoline oils are formulated differently and feature different lubrication requirements.
Check out this quick comparison chart.
| Feature | Diesel Engine Oil | Gasoline Engine Oil |
|---|---|---|
| Emissions | Creates a lot of soot and combustion by-products | Doesn’t produce a lot of soot |
| Additives level | High additives volume | Lower additives volume |
| Viscosity | High viscosity | Low viscosity |
| Detergency | Higher detergency | Low detergency |
| Replacement intervals | Needs fewer oil changes | Needs more oil changes |
Emissions & the Catalytic Converter- Diesel Oil vs Gas Engine Oil
A catalytic converter is an exhaust system element with porous metal filler. It is located between the engine and the muffler and converts toxic emissions from the engine to stable by-products before they enter the atmosphere.
Some combustion by-products like phosphorous, lead, and zinc can reduce the converter’s ability to deal with this problem.
Diesel oil boasts a high anti-wear in the form of zinc dialkyl dithiophosphate (ZDDP). The converters in diesel engines can deal with this problem, but the gasoline systems cannot.
This is one of the reasons why you should refrain from using diesel oil in your gas engine.
Diesel Engine Oil vs Gas Oil Additives
Diesel oil has more additives than gas engine oil; the most prevalent are over base detergent additives. The additives help the engine operate under greater stress and higher temperatures.
The detergent additive mainly helps neutralize acid and clean the engine since diesel oil creates a lot of soot and combustion by-products. Thanks to these additives, you don’t have to change diesel oil quite often.
Adding extra additives to a gasoline engine can lower its efficiency and performance.
Viscosity Diesel Oil vs Gas Oil
Viscosity is a very important property of engine oil. Getting the right viscosity for your vehicle’s engine is of utmost importance.
Generally, diesel oil has a higher viscosity than gasoline oil. Therefore, several issues might arise if you put this high viscosity in a gasoline engine.
The problems include heat generation from internal fluid traction and poor pumpability of the high viscosity during cold starts.
Always remember that your engine oil viscosity needs to be pumpable at the lowest temperature while protecting the engine’s components at the in-service temperature.
Will Diesel Oil Hurt a Gasoline Engine?
Using diesel oil in a gas engine can harm your car. The oil can cause several problems, including increased wear and tear and fuel inefficiency.
Gas engines require oils that can work at lower temperatures and with less stress. Diesel oil is the complete opposite of this – it provides lubrication for engines operating at high temperatures and compression ratios.
Additionally, diesel oil contains more additives that can damage gas engine components like catalytic converters, spark plugs, and sensors.
When Should I Use Diesel Oil in My Gas Engine?
If your gas engine is modified to produce more horsepower, diesel oil is one of the best options. This is because most modified engines require a higher viscosity to withstand stress.
You can also use diesel oil if dealing with a mixed fleet. For instance, if you have a diesel-powered RV with a gas-powered generator, using diesel oil that meets both engines’ specifications and viscosity requirements is your best bet.
Diesel oil also comes in handy for persons living in cold winter weather.
Is Using Diesel Oil in Old Gas Engine Good?
Diesel oil is thicker and more viscous; hence good to use in an old gasoline engine. It provides better lubrication for the older engine with more wear and loose tolerance.
However, it is important to note that not all diesel oil will work with your older gas engine. In fact, some can lead to more engine damage or total engine failure.
Therefore, if you intend to use diesel oil in your old gas engine, consult the manufacturer’s manual or a trusted mechanic to determine whether the oil suits your vehicle.
Can I Use 15w40 Diesel Oil in Gas Engine?
You can only use the 15w40 diesel oil in a gas engine if the oil is compatible with that particular engine. The 15w40 is a very high-viscosity diesel oil that can damage your gasoline engine if used wrongly.
Therefore, before adding it to your engine, check the owner’s manual for specifications. You can also consult a professional mechanic to determine whether the oil is appropriate for the engine.
Never use the 15w40 diesel oil in an incompatible gas engine, as it can damage the fuel system or clog the oil filter.
Is Using 10w-30 Diesel Oil in a Gas Engine Safe?
Using the 10w-30 diesel oil in a gas engine is only safe if the oil meets that particular engine’s appropriate specifications and viscosity.
Do not use the oil unless you are sure it is compatible with your gasoline engine; otherwise, you might do more harm than good.
Is it Possible to Use Diesel Oil in a Petrol Engine Car?
Although it is possible to use diesel oil in petrol engines, it is not recommended.
Just like gas engines, petrol engines operate at different temperatures and pressure than diesel engines. As such, they require oils with different viscosities and additives.
Using the oil in a petrol engine can lead to potential engine damage.
Overall, you should always use the oil specified in the manufacturer’s manual in your petrol engine for optimal performance and longevity. If you have questions about the oil to use in your vehicle, it is recommended to consult the engine’s manufacturer or a trusted mechanic for guidance.
