Tag Archives: gasoline

What Is The Difference Between Gasoline And Diesel?

Gasoline and Diesel are both types of fuel used to power all types of vehicles and equipment.  Gasoline and Diesel are also often sold at the same gas station, so what is the difference between gasoline and diesel?  For this discussion we will compare the similarities and differences between petroleum based gasoline and diesel.  There are different types of diesel fuel available, like bio-diesel, which I will discuss in a  later Difference Between post.

Difference in Refining

The difference between gasoline and diesel begins with how it’s produced.  Petroleum is refined to produce gasoline and diesel, but the type of fuel is decided at different refining points.  Crude oil, which is the thick black stuff you see exploding from oil wells, is refined in a chemical process.  Think of the process as like a tower and time spent refining yields a different product from the same crude oil.  During the process the crude oil is refined into Heavy Gas Oil, then Lubricating Oil, and then into Diesel.

Diesel fuel takes less time and is lower on the refining process, which typically leads to it being lower in price.  The next step of the refining process produces Kerosene and then finally Gasoline which is used in your car.  This is a simplification of the refining process, which also includes removing impurities, and lastly involves treating the fuel with additives, generally to increase octane rating.

Rating Difference

Typically when fueling up at the gas station you will notice different octane rated gasoline.  Diesel fuel is not measured by octane rating, rather by a cetane rating.  The ratings are similar in that they are used to rate the combustion quality of the fuel.

Use Difference

Diesel and gasoline are not interchangeable.  Gasoline engines are specifically designed to operate with gasoline properties and diesel engines are designed to operate under diesel fuels properties.  Using diesel fuel in a gasoline engine and vice versa could damage your engine.

In addition, gasoline will gel at a much lower temperature than diesel fuel.  This is why during the winter time, diesel vehicles will some times be plugged in, to allow a heater to keep the fuel above it’s gelling temperature.  This core heater will allow for a much easier start in frigid temperatures.


This has been a post into a series of articles on explaining entry level questions to automotive enthusiasts.

Other Difference Articles:

Difference Between Halogen and HID Lights

Difference Between Turgo and Super Chargers

Difference Between Hybrid and Regular Cars

Difference In Higher Octane Gas

High Octane Gas

High Octane Gas

Every time you fill up your vehicle you are greeted with several different fuel options, assuming that you have a gasoline engine.  Other than price, you may be interested in knowing what the difference is in higher and lower octane gas.  Rest assured that most modern gasoline engines are capable on running anything from 87-93 octane rated gasoline.  But lets look at the benefits, if any, of buying the higher octane gas.

Low Octane Gas Is Fine In Most Cases

That’s right, to the general driving public low octane gasoline will be just fine.  87 octane gasoline will perform just as well as higher octane gasoline, in a common daily driver.  There are a few exceptions that exist, so let’s take a look at what make the higher octane gasoline worth the money.

Cure Pinging With Higher Octane

A common noise amongst engines is a ‘Pinging’ noise coming from the engine.  This is caused by the gasoline entering the engine and not igniting at the correct interval.  Over time this pinging can cause long term damage to your vehicles engine.  In most cases running a higher octane gasoline in the vehicle, even for a short period, can help alleviate some if not all pinging.

High Performance Needs

Another need for burning a higher octane gas is dependent upon the type of vehicle you drive.  Higher compression engines require a higher octane gas to perform properly and in some cases even gain horsepower.  This only applies to a tuned engine, specifically designed for a higher octane.

My 99 Mustang GT engine required 93 octane to operate properly and not ping.  My engine was beyond stock and had enough modifications to justify the bigger expense and translate into marginal power gains.  Basically, you should know if your car requires a higher octane to operate properly, if not, then don’t worry about the additional expense.


The difference in higher octane gas and lower octanes is marginal enough that the common driver need not spend the extra dough.  I would recommend always filling up with the cheap stuff, unless you know specifically that your car needs the extra sweet juice from the pump, assume it doesn’t.


This has been a post into a series of articles on explaining entry level questions to automotive enthusiasts.

Other Difference Articles:

Difference Between Automatic and Manual Performance

Difference Between Halogen and HID Lights