Fuel Manufacturing 101: How Vehicle Fuel Is Actually Made Ready For Your Car

As someone interested in optimizing the performance of your vehicle, you are aware that there is a lot required for the proper functioning and maintenance of your engine. Fuel is the most important provision you supply for the use of your car, but can often be overlooked as a basic requirement. The truth is that you can get a lot more out of your car if you select the correct fuel.

First, let’s go over what fuel actually is because baseline knowledge of fuel production will help you to assess the intended effects of different fuel stocks and additives.

Fuel Types

 The refining process of crude oil can produce the following popular fuel types:

  • This is the most common source of fuel for vehicles. Additives are blended with gasoline to meet performance and environmental standards.
  • Diesel fuel is a popular choice for larger vehicles, trucks, buses and trains. Diesel fuel vehicles tend to be more fuel efficient than average gasoline vehicles and produce less carbon dioxide. It is also simpler to create than gasoline because it requires less additives.
  • Liquefied Petroleum. Liquefied petroleum, more commonly known as propane, is a clean fuel alternative to diesel and gasoline. Propane is less expensive than gasoline and diesel, produces less emissions, and can be used in hybrid cars.

This post will focus primarily on the production of gasoline, as it is the most commonly used fuel source for modern cars.

Fuel Production 101

Fuel production begins with crude oil, also called petroleum, which is created by the compression and heating of organic materials (hydrocarbons) over millions of years beneath the earth’s surface. Big oil companies spend billions of dollars per year in their quest to find and extract crude oil. Once a reservoir has been identified, a methodical drilling process begins. The extracted crude oil is transported to oil refineries where it is refined and broken down into light oil blendstocks. These are then treated to produce the gasoline that you purchase at the pump.


Distillation occurs when crude oil is placed into a distillation tower or column and heated until it separates into different components – “fractions.” Since crude oil is made up of different hydrocarbons (organic materials) it requires various temperatures for the fractions to boil off. Not too long ago, the distillation process represented the end of fuel refining, and the separate fractions would be shipped off as end-products. However, higher performance engines and technological leaps have resulted in further refining processes.



Fuel for automobiles and jets must undergo further processing. During conversion, the larger crude fractions separated in distillation are further broken down, typically using one of three processes: fluid catalytic cracking, hydrocracking, and coking. Each method produces different results.

  • Fluid catalytic cracking (FCC) is a frequently used process used to separate a heavier crude fraction into the light oil blendstocks required to make modern motor oil. FCC has lower operating costs than the two others.
  • Hydrocracking is not as cost-effective, but is extremely efficient at converting most of the crude fractions to light oil gasoline blendstock with minimal sulfur content.
  • Coking is a non-catalytic conversion process, unlike the other two, and is ideally suited to converting the heaviest types of crude oil fractions. Coked oil produces lower quality blendstocks.

Distillation and conversion combined result in the following types of blendstocks: naphtha, natural gasoline, isobutane, ethanol or methanol.

Upgrading and Treating

Now that the larger crude oil fractions have been broken down into the blendstocks required to create transportation fuel, they are often upgraded to transform the molecular structure so that they are higher-octane and lower-sulfur.

These two components are highly controlled because octane is necessary for decreasing the volatility of the gasoline. Sulfur interferes with emission control systems and is controlled by environmental regulations. It also tends to contribute to bad odor during use.

There are five major upgrading processes: reforming, alkylation, isomerization, polymerization and etherification. Each process is best suited for a specific type of blendstock. Reforming and isomerization are most often used for transportation fuel blendstocks.

Chemical Blending

Next, oil refineries blend together different types of blendstocks – hence the name blendstocks – in order to achieve a mixture with the desired chemical constitution. Blending helps companies to produce gasoline of the intended density, volatility (octane-rating), sulfur content, aromatics, and smoke point. The octane rating that you see on gas pumps is typically a result of this process.


The gasoline you use may be a blend of 6-10 blendstocks, including plant-derived ethanol. In fact, ethanol is added to almost all of the gasoline in the United States in order to meet environmental standards. Once blended, additives are used to increase the performance value of the gasoline. Each major oil company will have their own proprietary blend of additives.

  • Ferox, ferrous picrate, and oxyhydrogen may be added to improve fuel economy and reduce emissions.
  • Tetraethyl lead, methyl tertiary-butyl ether and ferrocene are octane-boosting additives.

There are also fuel-injector cleaner additives that help to counter the gunk that ethanol can create. Fuel stabilizers help to keep gasoline stable so it does not evaporate or decompensate when not being used. Many additives can be purchased and used separately from your gasoline, and it is worth looking into if you are looking for optimal performance and longevity from your car.


As you can see, a lot goes into the fuel that you use in your car. Researching the process by which major gasoline brands obtain and produce their fuel will help you to make sure that you are getting the best quality fuel for your vehicle.


Saara Pearson 

Saara is a car and auto enthusiast who loves everything to do with vehicles. She’s been studying to become a mechanic and enjoys tinkering on her vehicle of a weekend to see how things work. She works for 247spares.co.uk, enjoys life and loves going to the car races every chance she gets.


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