When you pull your car up to the fuel pump, the chances are you reach for the normal gasoline pump without even thinking about it. If you are in a semi-truck, or even some large heavy-duty trucks, on the other hand, you may need to get the diesel.

Have you ever wondered why the vast majority of regular cars and SUVs use gasoline but virtually all heavy-duty vehicles use diesel? If so, read on to get the answer.

To start with, it is important to understand that both of these fuel options work in a similar way. They get mixed with air and then put into the engine where they are ignited in order to push a piston, which is what causes the wheels on the vehicle to rotate.

The big difference is how the fuel-air mixture is ignited.

For gasoline, the fuel is ignited using a spark plug. This spark plug creates an electrical arc at the exact right moment to ignite the fuel and cause the controlled explosion that moves the piston. This happens thousands of times per minute within the engine, allowing your car to perform the way it should.

Diesel fuel is harder to ignite using a spark or even a flame, and once it is ignited, it burns somewhat slower. Diesel fuel will ignite, however, when it is put under high amounts of pressure, which is how diesel engines work. The diesel is put into the engine where it is compressed to build up pressure until it ignites.

Using the pressure rather than the spark plug has a few advantages. First, there is no need for spark plugs or the equipment that controls them, which makes the vehicle simpler. Second, since the engine needs to be able to handle higher levels of pressure, they are made with stronger materials that can last a lot longer.

On average, diesel engines can go many hundreds of thousands of miles without a problem, which is rare for a gas engine. Since semi-trucks and other large vehicles are generally used to go long-distances, this is important.

Another advantage is that diesel engines get better fuel efficiency. When traveling at such great distances, being able to get even a few more miles per gallon is essential.

Why aren’t all vehicles diesel then? Well, diesel engines have higher compression levels, which means they run hotter and noisier than diesel engines. Most people prefer the quieter gasoline engines, and since families often use gasoline cars, having them run cooler is a little safer.

In addition, diesel engines produce more dangerous pollution that has been linked to various human health issues, so keeping them out of garages and other confined spaces where people are is a safety issue.

Of course, each individual situation is unique, so there are options for diesel-powered family cars out there. In addition, electric vehicles, and even other fuel options, are available and becoming more popular every day.

This is really interesting, I never knew!

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