You may be surprised to learn that there are not that many engines that power trucks, especially large ones. Most of them choose chassis from manufacturers such as Kenworth, Peterbilt, Freightliner or Mack, and then install a diesel engine of their choice. The main engine manufacturers include Paccar (Kenworth & Peterbilt), Volvo, Mack, Cummins and Detroit. In fact, there are no other major manufacturers that produce engines for trucks, so the names above will make up most, if not all, of this article.
In addition, we have included big names from Europe, Asia and Australia, as their trucking industry is almost on par with ours and they also have excellent offerings. Just like choosing the right truck engine for your needs, picking the right game in an online casino matters. You can get started with a Stay Casino promo code to try different games and see what works best for you
Mack MP8 – 505 hp
Let’s start with an old reliable workhorse – the Mack MP8. Although it is the least powerful engine on our list, it still develops a very respectable 505 horsepower and produces 2521 Nm of torque.
The MP8 engine can be installed on every heavy-duty Mack truck, from day and sleeper semi-trucks to garbage trucks and specialised construction vehicles. Another engine that competes with the Mack MP8 is the DD15 from Detroit Diesel engines, which also develops exactly 505 horsepower but has less torque at 2508 Nm. Mack, which recently changed its fan-favourite bulldog emblem on the bonnet, claims that the latest generation MP8 is 40 kg lighter and therefore has a 5% better MPG (miles per gallon) rating when operating in automatic mode. In addition, to comply with increasingly stringent EPA (US Environmental Protection Agency) regulations, Mack has made some changes to its diesel exhaust fluid (DEF) after-treatment system.
Paccar MX-13 – 510 hp
The MX-13 is manufactured by Paccar for its Kenworth and Peterbilt brands and is found in iconic semi-trucks such as the Kenworth T680, 880 and W990, as well as the Peterbilt 567, 579 and 589. For many years, Kenworth and Peterbilt trucks offered the Cummins X15 diesel engine, but some time ago, Paccar began manufacturing the MX-13 and combining it with the Peterbilt and Kenworth lines. Since then, the MX-13 has been the standard option for all Peterbilt and Kenworth heavy-duty trucks, although it is worth noting that many trucks still use the Cummins X15 engine, which is available as an optional upgrade. The MX-13 has a maximum torque of 2,508 Nm – the same as the Detroit DD15 – and develops 510 horsepower from a 12.9-litre inline six-cylinder engine.
Detroit DD13 – 525 hp
Next on the list is the 12.8-litre DD13 engine, an inline six-cylinder that somehow manages to deliver 2,508 Nm of torque and up to 525 horsepower peak power.
You will find this engine in vehicles such as the fourth and fifth generation Freightliner Cascadia, as well as the Western Star 47, 49 and 57 series semi-trucks. This is a Class 8 diesel engine with a fixed geometry turbocharger, which has been significantly redesigned for the latest generation with additions such as swirl pistons, front and rear engine power take-offs (FEPTO & REPTO) and a new aftertreatment system. It also gets a new 10-pin injector system capable of asymmetric injection, which in turn reduces engine regeneration cycles, significantly increasing the DD13’s durability. Detroit claims that all these changes allegedly improve MPG by approximately 4%, although no actual data is available yet.
Cummins X15 – 565 hp
Perhaps the most legendary engine on this list, the Cummins X15 diesel engine develops a respectable 565 horsepower and a whopping 2,779 Nm of torque from a 14.8-litre inline six-cylinder unit.
Interestingly, this is not the largest engine Cummins manufactures, as Cummins also manufactures engines for trains, but it is certainly the company’s largest truck engine. The X15 is EPA 2024 certified and meets Greenhouse Gas Phase II requirements. Cummins has also used over a million miles of test data and developed a system that predicts the service life of all X15 consumables, such as fuel filters, urea filters, diesel particulate filters (DPF), oil filters and even the oil itself.
All X15 engines will also have access to Cummins’ Connected Solutions (CCS), patented software that helps with over-the-air (OTA) software updates and remote diagnostics. In addition, all X15 engines are programmed to work with Guidanz, Cummins’ technology service package. You’ll find the Cummins X15 in trucks such as International’s LT and HX lines, Freightliner’s Cascadia line and, of course, Peterbilt and Kenworth’s heavy-duty trucks, such as the 589 and T880. Considering that all of these models are bestsellers, there is a good chance that the big trucks you see on the road are powered by a Cummins engine.
Cursor 13 – 570 hp
Now let’s move on to our first non-American engine, the Cursor 13, developed by FPT Industrial, which is a subsidiary of the huge IVECO group. IVECO manufactures the Cursor 13 in several versions, including one for heavy-duty trucks. As of 2025, the Cursor 13 truck engine is available in six different power ratings, starting at 302 kW (405 horsepower) and 2125 Nm of maximum torque. The most powerful version of the Cursor 13 is approximately 50% more powerful, as it can develop up to 600 horsepower and 2403 Nm of torque and was designed to power trucks with a gross vehicle weight of 16 tonnes and above.
Detroit DD16 – 600 hp
One of the most popular engines on the market is Detroit’s 15.6-litre inline six-cylinder DD16, which develops 600 horsepower and 2779 Nm of torque.
You’ll find the DD16 in Western Star’s 49XX and 57XX models and in Freightliner’s latest generation of Cascadias. The DD16 is definitely the most powerful and technologically advanced engine Detroit makes, and it impressively continues to meet new emissions standards. The DD16’s fuel injectors have a standard operating pressure of 262,000 kPa (38,000 PSI) thanks to a new enhanced common rail injection system (ACRS), which results in more efficient and cleaner combustion overall. In addition, the DD16 features a unique twin-turbocharger layout, using a turbocharger for primary engine power increase and a secondary exhaust turbine.
Mercedes OM 502 LA – 612 hp
If you’ve seen a Mercedes truck, it was probably an Actros; and if you’ve seen an Actros, it was probably paired with a Mercedes OM 502 or OM 501 engine.
The OM 501 develops less power (435 horsepower) than the OM 502, which is currently Mercedes Trucks’ top offering. The 502 LA, which is the larger of the two Actros engines, develops 450 kW (612 horsepower) and 2700 Nm of torque from a 15.9-litre V8 block, which is paired with a 12- or 16-speed G-series PowerShift transmission, also from Mercedes. Together, this pair can offer many great features to European long-haul drivers, such as higher speed reversing, extended cruise control settings from 2 km/h and above, Rock-Free mode for driving on rough terrain, and direct shifting from first gear to reverse gear, bypassing the neutral position.
In addition, most 502 engines will also meet Euro emission standards, with all engine systems controlled by an engine management system (EMS) called ‘Telligent’. Another notable feature of the Mercedes 502 LA is that, like the DD16, recirculated exhaust air is used to produce additional power for the engine when under heavy loads. The only difference between the DD16 and OM 502 LA systems is that Mercedes uses not one but two exhaust gas turbochargers and a pump unit system (UPS). It’s nice to see Mercedes supporting this engine, as it allows the use of flat-nose semi-trucks, which have almost disappeared in America, and who knows if these beautiful machines will ever make a comeback.
MAN TGX D38 – 660 hp
MAN trucks are mainly sold in Europe and manufactured in Germany, as MAN is a subsidiary of the Volkswagen group, which also owns many other brands. So it makes sense that MAN’s largest trucks, such as the TGX range, would be equipped with MAN’s most powerful engine, the D38. The full technical name of this engine is – get ready – MAN D3876 LE12x, but in the industry it is referred to as the D38 for simplicity. It is available in three main versions: 565 horsepower, 612 horsepower and 660 horsepower, with corresponding torque variations. The displacement of all versions is at the upper limit of European standards – 15.26 litres in total, producing a staggering 3000 Nm of torque at 2500 bar (36,260 PSI). The engine fully complies with the latest EPA and/or CARB regulations and was presented at the IAA Nutzfahrzeuge exhibition in Germany.
Volvo D17 – 780 hp
The Volvo D17 is the latest engine from Volvo Trucks and is actually the unit with the largest displacement on our list – 17.3 litres, developing 780 horsepower and 3,802 Nm of torque.
The engine has not yet been released on Volvo’s domestic market in Europe, but has been undergoing road tests in Australia since the beginning of this year. Presumably, these are test rigs collecting data on the use of the D17 engine, most of which will power Volvo’s FH series of long-haul trucks. The D17 is set to be a step up from Volvo Trucks’ current top-of-the-range engine, the 500 hp and 2,237 Nm D13. An important feature of the D17 is that you can choose from three types of fuel: diesel fuel, the recently introduced renewable fuel called HVO, and a future version that will also run on 100% B100 biodiesel.
*HVO (Hydrotreated Vegetable Oil) is a renewable diesel fuel produced from vegetable oils, animal fats or waste oil.
Weichai WP17H – 800 hp
The Weichai WP17H is the most powerful diesel engine ever installed in a production truck. Used in the Shacman X6000, it develops 800 horsepower and 3754 Nm of peak torque. This configuration is widely recognised as the most powerful production truck in the world, although it is unclear whether Weichai or Shacman intend to expand the range. A notable feature of the Weichai WP17H engine is that it is designed for a service life of two million kilometres (approximately 1.24 million miles) of continuous operation.
Currently, Shacman with Weichai engines is manufactured and used in China, but is also sold in Russia, and there are potential expansion plans targeting Argentina and the rest of Latin America. Returning to the dreadful Weichai WP17H engine, the truck option is a 16.6-litre four-stroke V8, undoubtedly one of the largest V-8s in the world, and has a host of other configurations, including those specialised for cranes, agriculture, mining and construction. There’s really nothing else to say about the WP17H – it’s big, powerful, has plenty of torque, and we can only hope that one day Paccar, Mack, Cummins or Detroit will give us something to match it.
So there you have it, the 10 most powerful diesel engines ever to power a semi-truck. From flatbed trailers to specialised rigs, these are the engines that keep heavy industry moving around the world, and now you have an interesting topic of conversation for your next family dinner.
