A V8 is one of the most heard of engines in the world and not uncommon in semi trucks.
The power delivered by a V8 engine is exactly what a truck needs to pull the 80,000 Ib weight.
We are going to take you into how fuel-efficient they are, which trucks have the best V8 engines, and who makes them.
We’ll leave no stone unturned on these amazing machines.
Here’s a short answer to whether Semi Trucks have V8 Engines:
Semi trucks have V8 engines with Detroit Diesel, Caterpillar, Scania, and Mack being amongst the top manufacturers of V8 engines. V8 engines have good power and fuel efficiency and have been used to power up semi trucks for decades as another alternative to the inline six-cylinder engine.
Table of Contents
Do Semi Trucks have V8 Engines?
They do have V8 engines but most are inline 6 cylinders (I-6 for short) because they’re a straightforward design with fewer components and produce more torque than the V8 does.
Truckers prefer the high torque over high horsepower and the more torque they have the lower the revs which in turn prolongs the life of the engine.
It is also easier to maintain an I-6 engine.
The main reason for more inlines over V8s is they are cheaper to manufacture.
Are V8 Engines in a Semi Truck Diesel or Gasoline?
Semi truck V8 engines tend to be diesel because they have increased power at lower speeds than a gasoline engine does which is noticeable first and foremost when driving uphill.
Fuel efficiency on diesel engines is a good reason to choose a V8 over an inline 6 although the I-6 can be just as efficient, however, efficiency partly depends on the skill of the driver.
Truck companies and owner-operators tend to choose the right engine for their needs.
How much Fuel do Semi Truck V8 Engines Use?
The amount of fuel a semi truck will use varies depending on how it is driven, the road conditions, if the truck has a load, and what condition the truck itself is in.
Let’s assume the truck is driven well and has an average daily load and is well looked after, in this case, a truck can get 7 miles to the gallon and in some cases like the Scania R530 can reach records of up to 8 mpg.
Are V8 Engines in a Semi Truck Efficient?
The transition from gasoline to diesel has been going on since the early 1950s when manufacturers noticed the difference in how diesel would burn slower than gasoline.
A V8 semi truck engine is fairly efficient when you consider what they are used for.
They have a fast spin on the crank and better balance with smaller pistons which gives a shorter stroke.
V8 diesel engines are approximately 25% more efficient than V8 gasoline engines.
However, inline 6 cylinder diesel engines generally tend to be more efficient than V8 diesel engines as it produces more torque at a lower RPM.
How much Power and Torque does a Semi Truck V8 Engine have?
Truck drivers care about their comfort and style a lot but the other thing they hold in high regard is the power of the engine to get the job done and V8 engines do not disappoint.
A Scania R730 for example has 730 horsepower and a torque of 3500 Nm on a 16.3 litre V8 engine this impressive power can get 7.84 mpg on highways and 7.32 mpg on tougher roads.
There are many different trucks with various horsepower and torque, choosing the right one for your needs is our best advice.
Are Semi Truck V8 Engines Reliable?
A V8 semi truck engine is as reliable as any other well-looked-after engine on the market although there are people out there that say a V8 is the most reliable they have ever had.
Bulletproof is the saying for these magnificent beasts some say these engines are so reliable that it would take some serious abuse for them to become unreliable.
Are semi truck V8 Engines Loud?
Diesel engines are generally louder due to the higher compression ratio. On average a semi truck will produce around 100 decibels of sound or noise as most will call it.
The V8 in particular has one of the loudest roars an engine can produce and it is down to the timing of the cylinders that gives it its distinct sound.
Workshops and manufacturers are slightly concerned by the noise of their workspace because it creates an unsafe environment for the staff through a lack of being able to communicate effectively.
This can lead to delays in the production line and a slower response time in dangerous situations.
Are V8 Engines in a Semi Truck more Complex?
A V8 engine in any calling is going to be more complex due to its size and its V shape structure however the advantages are its smaller size and lower center of gravity for the engine.
However, the size of the engine doesn’t matter too much in a semi truck as semi trucks have sufficient space in the engine bay to accommodate an I-6 engine.
The disadvantages are they require more parts and more maintenance and in the line of work you are in you want the least amount of downtime possible, that’s not to say they’ll go wrong.
They will drive just fine so long as you regularly maintain them but will take a little longer at the workshop than an I-6 would.
Are V8 Engines in a Semi Truck Easier to Maintain?
In terms of maintenance, there are some real differences in inaccessibility to the engine parts.
An inline engine would have easier access to the extended engine components and have less to go wrong.
A V8 engine is a little more complex in design-build and will therefore be can be more intimidating to fix if something goes wrong.
It has more components such as two manifolds and two turbos with a complicated design that would be more difficult to maintain, and more expensive to fix.
However, you shouldn’t have any issues with maintaining or fixing a V8 or I6 engine, so long as you use a reputable mechanic who knows his stuff.
Are V8 Engines for a Semi Truck Expensive to Make?
Some manufacturers find it more expensive than others, some buy their components and then assemble them on site which is more costly to them and others mold their own.
Either way, you approach the build of an engine it is one of the most expensive parts of the truck but worth every penny as it is also the heart and soul. It will generally see you through to the end of the truck’s life.
The rise in price for materials the engine parts are made from such as cast iron, aluminum alloy, and alloy and structural steel adds the expense of its build.
The manufacturing process itself is a lot more complexed than any other vehicle engine and uses more materials and working hours which will inevitably result in more expenses.
Do V8 Engines take up More Space than a Straight 6 Engine in a Semi Truck?
V8 engines are shorter and wider than an I-6 engine since it has 4 cylinders in a row. An I-6 o the other hand has 6 cylinders in a row, and therefore longer and narrower.
However, the size of either engine is not of concern when fitted in a semi truck due to its large engine bay. The size of the engine bay is only of concerning smaller vehicles such as cars.
They do take up more space because of their shape where a straight 6 is much narrower and fits between frame rails with ease allowing more space for other things like a turbo and filters.
Are V8 Engines Better than Inline 6 Cylinder Engines in a Semi Truck?
This would depend on who you ask as there are different opinions on this subject it will also depend on what the truck is being used for and who has made the engine.
An inline 6 cylinder engine has a stronger bottom which allows for longer strokes, it has less vibration as the pistons are more in sync and will have more of a natural balance.
The inline 6 will have less wear on the engine from its lower rpm meaning an increase in fuel economy but suffers from heaver parts which can eventually destroy the engine.
A mechanic’s opinions on the V8 are that it doesn’t belong in diesel form and they hand the title to the inline 6, but that is just an opinion, what do you think?
Inline 6 diesel engines are generally preferred, however, there are manufacturers that employ the V8 diesel engines really well in their semi truck design.
Which Semi Trucks have V8 Engines?
Here is a list of semi trucks with V8 engines old and new:
- Scania R730
- Mack E9
- Peterbilt 1980 359 model
- Kenworth 1980 W900A
- Scania 660S
- Scania R580
- Scania 530
- Scania 770S
It is clear to see from the list that Scania loves a V8 in their trucks they believe in high performance and require a good balance of efficiency and power that only a V8 can deliver, what would you prefer?