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What Kind Of Fuel Do Semi Trucks Use? (15 Cool Facts)

The preferred choice is Diesel in semi trucks but it may not remain that way much longer with the competition.

Manufacturers are beginning to embrace propane fuel in some of their trucks.

We’ll take a look at which is better and why propane isn’t fully integrated into the trucking industry yet, what green/red diesel is used for, and much more.

Here’s a short summary to what kind of Fuel Semi Trucks Use:

The most common types of fuel that semi trucks use are diesel, propane, and gasoline. More than 90 percent of semi trucks use diesel fuel since diesel engines have good fuel efficiency, power, and torque. The most popular diesel fuel used by semi trucks in the U.S. is Diesel #1 and Diesel #2.

What Fuel do Semi Trucks Use?

Semi trucks mainly use diesel fuel for their efficiency.

Diesel produces more energy than gasoline overall this is much needed to haul heavy goods over long distances and up and down steep hills.

The power to weight ratio in a semi truck diesel engine is greater than a gasoline engine.

Are Semi Trucks Gas or Diesel?

Most engine manufacturers go for diesel on their engines because the fuel efficiency will usually increase their sales.

The more efficient the engine the more sort after it is.

Diesel lubricates the engine better which makes the engine last longer, another unique selling point.

Gasoline burns quicker cost more and cause more wear on the engine.

What Kind of Gas does a Semi Truck Use?

There are three types of gasoline at filling stations and choosing the right one for your semi truck is relatively easy, you can check the owner’s manual for which one to use.

There is regular (87) gas with low octane fuel generally used for cars, midgrade (89-90) with a middle range octane used for vans and small trucks, RV’s and some semi trucks, or the premium high octane (91-94).

Technically you could use any of these fuels on your semi truck, it is best to check which one will suit your truck first.

What Kind of Diesel does a Semi Truck Use?

The standard diesel fuel found in any motor vehicle is Diesel #2 and is used globally for its great fuel economy the temperature of the diesel when at its hottest is tested.

The fluid that causes the least resistance and flows to lubricate all the vital engine components is the number one choice, diesel is broken up into 3 classes.

1D(#1) is used for cold weather as it has lower viscosity 2D(#2) is used for warmer weather and 4D(#4) is used in low speed engines.

Do Semi Trucks use Red Diesel?

Red diesel is just diesel that has been dyed due to its chemical properties being high in sulfur.

Semi trucks do not use this fuel as to do so would result in heavy fines and other penalties.

This fuel is used for off-road vehicles and generators and is actually illegal to use on any road vehicle, probably best to leave it to construction and agricultural equipment.

Do Semi Trucks use Green Diesel?

Green diesel is also illegal to use in your truck.

It is reserved for home heating and shipping. There are two types of green diesel one is standard green diesel and the other is Sulfur Free Green diesel.

Sulfur free also referred to as Gas 10 is much lower in sulfur than the standard green this fuel can be used for agricultural machines and again the construction business.

Do Semi Trucks Run on Propane?

Some fleets are using propane to fuel their trucks because it is cheaper by up to 30% on gasoline and nearly 50% on diesel.

School buses use it frequently, it is a flexible fuel.

It can be used on a variety of vehicles from Class 1 cars to Class 8. It has been recorded that propane can operate a medium-size truck for 400 miles on a single tank of fuel.

Do Tanker Trucks use Diesel?

A tanker truck uses natural gas more like gasoline in its engines. A heavy-duty liquefied gas (LNG) it is supercooled and cryogenically stored in a tank on the side of the truck.

This fuel is used for its storage ability for long-range trips and is usually used for class 7 and class 8 trucks traveling far and wide.

Why do Semi Trucks Use Diesel?

The main reason is its efficiency diesel lasts longer than gasoline and coats the components of the engine better. It has also been proven that a diesel engine requires less maintenance.

A diesel engine provides more torque with a better power to weight ratio meaning they get the job done with less effort and until a new breed of truck is engineered, diesel will remain the champion.

What Percentage of Semi Trucks are Diesel?

The percentage for semi trucks using diesel is slowly going up every few years, it is currently at around 90% with the 10% reluctant to change from their current fuel.

Diesel remains king for unique qualities in durability, availability, zero emissions, power and reliability. With advancements in technology the diesel engine is leaps and bounds above the rest.

The engines are getting better and better with more torque and less fuel consumption and lower carbon emissions, the list seems to be endless it is very easy to see why semi trucks are diesel.

Can a Diesel Truck Engine Run on Propane?

Propane can be used to run a diesel truck but unfortunately, it can not run with the diesel still inside, this would cause your engine to eventually blow up because it works against itself burning one before the other.

To be successful in introducing propane to a diesel engine some changes have to be made.

First you would have to reduce the compression ratio which would involve a qualified mechanic.

Then you would need to introduce spark ignition (plugs) then the vehicle will be set up safely to use propane.

Can a Gasoline Truck Engine Run on Propane?

Gasoline truck engines can run on propane.

The engine itself doesn’t need modification. An extra tank has to be added and a switch to operate the change over of fuel from gasoline to propane.

The two do not mix as they burn at different rates, propane takes a lot longer to use up than gasoline.

I once took a car journey on LPG for 200 miles and only burnt around $35 now that’s impressive.

Propane doesn’t just last longer. It is cheaper to purchase and available just as much as gasoline or diesel is.

Is Propane More Efficient than Diesel?

Propane is more efficient, it burns slower than diesel and produces fewer greenhouse gases although it is not as famous to the common motorist. Propane is slowly making its way up.

It is used in school buses, recreational vehicles, forklifts, and skid steer loaders. It doesn’t degrade but is highly flammable and can cause serious problems when it leaks.

With no trace of an odor, it makes this invisible liquid quite dangerous.

Which Grade of Standard Diesel Fuel is the Best for Semi Trucks?

Diesel #2 is the common choice for semi trucks. It is more economical and less volatile than diesel #1.

Semi trucks are known for carrying heavy loads up and down the country. The trucking industry wouldn’t be what it is today if they had to pay through the nose for their fuel.

Diesel #2 keeps that cost down. You should also take into consideration the age of your vehicle.

Some vehicles that are older run more efficiently on diesel #1 where some newer models run better on #2.

You will get to know the difference once you study the two and make your own decision.

Which is the Most Efficient Fuel for Semi Trucks?

Efficiency can be greatly enhanced by not overloading your vehicle, sticking to speed limits, maintaining the correct tire pressure, and staying in a higher gear when possible.

One of the most effective ways to reduce fuel consumption is to use the most efficient fuel for your truck. Diesel is the most commonly used and most efficient fuel.

Propane would be used more as it lasts longer but to do a conversion on a semi truck would cost a lot of money and may end up being of no real difference in terms of savings.

Propane engines are made for medium-sized trucks but are yet to be fully introduced to the big rigs so diesel remains number one, for now!

Happy Trucking!