The Difference between Leaded, Unleaded, Diesel, and Bio-Diesel Fuel

Purchasing a vehicle is a long and sometimes challenging process, but choosing what gas goes into your car shouldn’t be! Keep in mind the fuel options you have when looking for a new vehicle. Different vehicles have different engines which require different types of fuel to ignite the engine. It’s good to know your options. 

The main difference between leaded and unleaded fuel is the additive tetraethyl lead. Leaded gas was commonly used many years ago but it was discovered that lead has undesirable side effects when lead is released into the air. Leaded gas was found to be harmful to the environment and humanity which resulted in the production of unleaded gas. You won’t find leaded gas at the pump. Nowadays its used for motor racing, heavy equipment, and marine vehicles. 

Unleaded fuel is also known as petrol or gas depending on where you live. Here in the United States, it’s typically called gas, while our neighbors up North in Canada call it petrol due to the engine type. The term “unleaded” means regular gas, diesel gets its name because it’s a completely different type of fuel. Petrol engines run off unleaded fuel by combining gas and air to compress and ignites the engine with a spark. This is significantly different than a diesel engine which only takes the air, then the engine compresses the air while injecting fuel into it which ignites the fuel. Unleaded fuel is most common, cheaper than diesel, and you see the prices fluctuate every day. 

Both gas and diesel are refined oils, made from petroleum, and most commonly used in motor vehicles. Diesel fuel contains no lead however unleaded gas used to contain led but nowadays it doesn’t. Diesel is made differently than unleaded by distilling crude oil. Vehicles with a diesel engine get on average 30% more mileage than vehicles that run off of unleaded gas but they produce more emissions. Although diesel engines are more efficient and produce 10-20% fewer pollutants they still produce a higher amount of greenhouse gases. If you’re looking for a vehicle with a lot of power and torque than a diesel engine will be best for you. 

The best thing about biodiesel is that it’s renewable. These days the environment has been the main focus and business are developing a way to convert plant materials into renewable fuels like biodiesel. Biodiesel is made from biomass which is typically made from vegetable oil and fat from animals. Another great benefit of biodiesel is that it can be used in regular diesel engines without harm to the engine. Biodiesel consumption is sustainable due to its availability to be produced, sold, and used. 

When you’re deciding on a new car remember to keep these different fuel types in mind. Unlike renewable fuel alternatives, fuel is limited and we can only produce a limited amount. If you are taking an environmentally friendly perspective it’s worth checking out other alternatives like renewable fuel or an electric vehicle. Check your owners manual to see which grade of gas to use. 

If you’d ever like more information on the best gas for your vehicle or about the alternatives, give American Five Star Auto Repair & Transmission a call or set up an appointment online. You can find us at 2070 E Apache Blvd Ste. 101, Tempe, AZ 85281 Mon - Fri: 8:00 AM - 6:00 PM | Sat: 8:00 AM - 1:00 PM. See you soon! 


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