Facts about semi-truck engines

May. 26, 2022

When it comes to semi-truck horsepower, the numbers can vary depending on the engine, truck size and brand. However, semi-trucks typically stay in the 400 to 600 horsepower range, making them very powerful machines. The higher the horsepower, the more worthwhile it is to consider factors such as aerodynamics, weight and fuel economy. Below, International Used Truck Center offers more information on powerful semi-truck engines, including answers to the "How many gallons does a semi-truck hold?" question. Learn more, then explore the trucks engine we have for sale!

Facts about semi-truck engines

Facts about semi-truck engines

Semi-truck engines are completely different from the engines found in regular cars, trucks and SUVs. They are larger and more powerful than regular engines, and require more oil and gas. Here are some interesting facts about semi-truck engines versus car engines.

The engine is one of the most important components of any vehicle, but it is particularly important in a pick-up truck. Pick-up trucks are designed to haul heavy loads and trailers. For work vehicles, the engine is responsible for getting the job done.

To help you figure out what you need, we've done our homework and come up with suggestions on how to Ruanze pickup truck engines and related products. These don't have to be the most powerful or biggest, we've picked out some four and six cylinder and large conventional V8s to help you narrow down your pickup shopping list.

What size engines are available for semi-trucks?

When we talk about semi-truck engines, we all know that they are powerful and the right size. Depending on the application, trucks can have engines as small as 6 or 7 litres.

Big rigs can struggle a bit with this size engine, so they use more powerful engines like 14, 15 or even 18 litres, which I know sounds crazy, but they do have a lot of heavy work to do.

Is a larger semi truck engine always better?

In terms of truck engines, bigger isn't always better, it's more to do with quality and what you will be using the truck for. You may find that having a larger engine is not so good when driving locally.

Nor is it a good idea to use a smaller engine when hauling logs or coal in the mountains. Our best advice is to match the engine size to the job you will be doing.

If you are considering the option of hauling more than one different type of trailer, it is best to do your research on the type of tractor that will suit your needs.

Which size semi truck engine is more reliable and lasts longer?

Reliable and long-lasting engines can be any size, and FAWDE is known for producing top-of-the-range engines with high mileage expectations, and they often deliver.

They range in size from 6.7 litres to 12.9 litres, which suggests that reliable engines come in all sizes, no matter what the brand, and a well maintained engine will last as long as you like.

There are many great engines out there, so whichever one you choose, make sure you look after it and it will look after you.

Is maintenance the same for all sizes of semi truck engines?

The length of time it takes to maintain a semi-truck is usually the same for all engine sizes. What differs, however, is what needs to be done, which depends very much on the conditions it is in.

Larger engines should not take any longer than smaller truck engines. Mechanics also add to the equation of how long they can take, so make sure you go to a reputable workshop.

Which size engine should you use for your semi truck?

Again, this depends on what you need it to do. The new mid-range engines offer excellent durability, efficiency and enough power to do most tasks.

The 13-litre produces around 500 hp and almost 2,000 torque.

10 factors to consider when choosing the best engine for your semi-truck

Type of work

Firstly, as an owner operator, you need to know what type of work you will be doing, for example

Average load weight

The type of terrain you will be travelling over

The type of trailer you will be pulling

Knowing the specifications of the rest of the drive line

Know what transmission and rear differential ratios

FAWDE as a truck engine manufacturer can provide you with a truck engine for your power needs under all types of work.

Size considerations

Bigger is better is somewhat of an outdated idea of thinking about the best truck engine.

Bigger horsepower is best, and that doesn't sound as true now as it once did.

Depending on the type of work you will be doing, bigger isn't always the best choice for a truck engine. I suspect there used to be more androgyny involved in many engine choices.

Since owner-operators are in business for profit, rather than bragging about their rights at the truck stop counter, the "smaller" engines (13 litres) are now much better than they used to be.

Most of these diesel engines can reliably reach 500 hp at 1850 TQ, which is a pretty impressive rating.

These motors are lighter and lighter on the tare than their 15/16 litre big brothers and can offer considerable fuel economy.

FAWDE can offer you more power and less weight in a truck engine.


Truck manufacturers have their own proprietary drivetrains.

All chassis manufacturers have their own brand of semi-truck engine available, so once you have chosen your truck manufacturer, your choice of engine becomes much easier.

As a truck engine development manufacturer, FAWDE not only powers our own truck brand FAW Trucks, but also carries out the supply of truck engines for truck manufacturers, truck hauliers all over the world.

Engine costs - short and long term

As the small owner operator business is primarily concerned with profitability, cost is critical.

The cost of a truck engine is the most immediate short-term cost.

Some manufacturers will offer special discounts for driveline combinations, for example for specific engine models with specific gearboxes and rear differentials, especially if it is their own brand.

Sometimes manufacturers will offer cash discounts or free extended warranties.

The long-term costs of an engine include

Fuel economy

Oil change intervals

Oil change costs

Overhead setting frequency and cost

Extended warranty costs

All these costs may vary from manufacturer to manufacturer.

FAWDE has a significant advantage in terms of fuel efficiency and cost of use through continuous product development and upgrading, and we have overseas marketing support branches to provide you with after-sales service and other services.

Truck engine repair and dealer network availability

Truck manufacturers are learning from the automotive industry that it is virtually impossible to perform any type of engine repair anywhere but at the OEM plant.

Therefore, as a new buyer, the dealer network and your relationship with the dealer may become a more important factor than the truck brand when choosing an engine.

We have our own dealers in countries around the world, or you can ask a FAWDE dealer directly


When you specify an engine for a new truck, the phrase "never say never" comes into play.

The type of work you now do as an owner operator will almost undoubtedly change.

Changing engines today is much easier than in the past.

Today's engines use the same block, heads and injectors to provide a variety of horsepower and TQ settings.

If you are pulling 80,000 pounds or less of the type of work you currently do, then 450-475 horsepower may be sufficient for your application.

However, if you have the opportunity to do triple or heavy loads, then you can upgrade your engine to 500 horsepower.

We have a high horsepower engine to provide you with all your power needs.

Fuel economy

The biggest single variable cost is fuel consumption.

Remember, bigger displacement and higher horsepower will cost more every time, no exceptions.

FAWDE has developed technology to give you the maximum amount of horsepower while controlling costs.

Tare weight

Smaller truck engines are lighter in weight.

If your industry requires minimal tare weight, then weight will be a very important factor in the engine and truck brand you need to buy.

FAWDE offers you truck engines for light trucks, medium trucks and heavy trucks with different needs

Long warranty

The cost of an extended warranty should be factored into the purchase cost of your truck.

Most warranties cover aftertreatment as well as the engine. Read the fine print.

Always make sure you understand the limitations of the warranty you are purchasing.

Make sure you understand your responsibilities as the owner so that it is valid for as long as you need it.

Your extended warranty is basically insurance.

FAWDE is the number one diesel engine manufacturer in China offering you quality products and excellent after sales service

Semi-truck engines are about six times more powerful than the engines in passenger cars.

On average, semi-trucks have a horsepower range of 400 to 600 hp and an average lb-ft torque range of 1,000 to 2,000.

Unlike passenger car engines, semi-truck engines can only be stopped for oil changes or engine service because of the anti-idle method.

Semi-truck engines have more than 12 gears instead of the 4 to 5 gears found in passenger cars.

The engine in a semi truck can hold about 15+ gallons of oil compared to the 4 to 6 quarts in a passenger car engine.

How many gallons of gasoline does a half tank hold? The range is between 125 and 300 gallons of fuel. To distribute the weight of the truck, there are actually two fuel tanks: one on each side of the tractor.

What is the best semi-truck engine?

As "China's power expert", Jiefang Power always strives to create high quality engines that best suit customers' needs.

FAWDE Aowei 520hp engine is the best engine for Jiefang Power to provide the best engine for the customers by deep plowing into the market segments of efficient logistics, express delivery, gravel material and coal hauling.

Facts about semi-truck engines

Engine fuel-saving: it has ten fuel-saving technologies such as industry-leading 2000bar high injection pressure and patented combustion chamber design.

Fuel saving of the whole vehicle system: Mainly equipped with Jiefang independent 12-speed AMT transmission, lightweight 435 axle, high horsepower and small speed ratio, no downshifting on slopes and more running in high gears.

Unique mature calibration: unique mature vehicle fuel consumption calibration technology, "low speed" does not cost, "high speed" special savings, 100 km strength fuel savings of 3%-5%.

Powerful: 2520N-m industry maximum torque, acceleration, overtaking more quickly; 800 rpm torque 2050N-m, more powerful start; suitable for high-speed, national roads, mountain roads, plateaus and other complex road conditions.

Super long oil change: 100,000 km long oil change as standard, less station, more operation, maintenance costs can save 2000 yuan.

The strongest brake: the first domestic generation of independent rocker engine brake technology, braking power up to 350kW, extending the service life of brake pads and tires and reducing the frequency of replacement.

Product quality assurance: Inherit the high reliable quality of classic Aowei engine, the first industry retention in the logistics market, high market recognition; the first product to obtain the Euro VI-e certification, strict development process, full product verification.

Manufacturing quality assurance: the first batch of national intelligent manufacturing pilot demonstration factory production, modern equipment automatic production and testing, to ensure product production consistency.

FAWDE engine products are exported to more than 80 countries and regions around the world, such as Southeast Asia, Middle East, Latin America, Africa and Eastern Europe. The brands include ALL-WIN, POWER-WIN and KING-WIN series, which meet Euro 2 to 5 emission standards and have many international export certifications. We have offices in 11 countries including South Africa, Indonesia, Iran, Vietnam, Russia, Chile, Pakistan, Mexico, Kenya, Philippines and Myanmar.

If needed, please contact us