10 Diesel Engines With The Highest Horsepower

Typically, when people think of diesel engines, they think about torque. Compared to their regular gas-powered counterparts, diesel engines tend to have lower horsepower and higher torque figures. This is mostly due to compression ratios. Diesel engines have higher compression ratios, which gives the engine more pulling power. Thus, you may see some weird figures on diesel engines if you've never really looked at them before. One good example is the 16.8-liter V12 on the MT845E tractor, which has a peak torqueof between 1,605 and 2,095 lb-ft. It's wild. 

With that said, there are some diesel engines with surprisingly high horsepower figures. The semi-truck segment is one such area where diesel engines routinely top 500 horsepower without breaking a sweat. Of course, those trucks also make upwards of 2,700 lb-ft of torque, so the old adage that diesel engines produce more torque is still relevant. For consumer-level vehicles — for which this list is made — the figures aren't quite that dramatic. When it comes to cars and trucks, that much torque is total overkill. 

So, what does a high-horsepower diesel engine look like? Well, you'll see most of them on work trucks from Ford, Ram, and GM, along with a few on sportier cars made by brands like Audi and Mercedes-Benz. Most of the powerful diesel engines in the world move massive equipment like semi-trucks and farm tractors, which we'll touch on briefly, but this list will remain mostly focused on consumer-level vehicles that you could buy at a dealership. 

Let's start the list with the Mercedes-Benz OM 656. This is a 2.9-liter inline six that has two variants. The 350 d variant outputs 286 horsepower while the slightly stronger 400 d variant outputs 340 horsepower and roughly 516 lb-ft of torque. Obviously, we'll be talking about the 400 d variant today. This is the strongest of Mercedes' OM engines, and it is the most powerful diesel engine that the company made. In addition, Mercedes was quite proud of the fact that it was not only stronger than the prior generations of diesel engines but also consumed 6% less fuel than outgoing models. Faster and more efficient is about as good as it gets. 

Mercedes has used this engine on a number of vehicles in its lineup, including the CLS-Class, GLC-Class, GLE-Class, and GLS-Class, along with G, E, and S-Class vehicles. It was introduced to the automaker's vehicles in 2017 and is still in use today. In addition to being surprisingly powerful for a consumer-level diesel engine, Mercedes packed quite a lot of technology into the OM 656. That includes two-stage turbocharging and the brand's Camtronic variable valve-lift control. The variable valve stuff can cause issues for some motorists, but it's neat technology. 

It makes sense that Mercedes hasn't made another OM engine in a while. This one has as much tech as possible to keep emissions low while also putting up some decent fuel efficiency. It boasts a base fuel efficiency of 5.1 liters per 100 km, which roughly translates to about 46 MPG. 

Next up is one of several diesel engines designed for trucks. GM has been making its Duramax diesels in partnership with Isuzu since the turn of the century. Among those was the GM 6.6L LBZ V8 Duramax Turbo Diesel. The name is longer than its production run, as GM only made this engine in 2006 and 2007. Around then, government emissions standards kicked in, causing most automakers to release new engines that worked with the new standards. Despite its short lifespan, it's widely considered to be one of the better Duramax diesel engines that GM has made.

One reason is that it had a lot of power for its era. It could make upwards of 360 horsepower and 650 lb-ft of torque, making it one of the best work truck engines of its era. As such, GM shoved this into exclusively trucks, including the Chevy Silverado HD and the GMC Sierra HD. The formula here is very simple. GM made this engine for trucks, and it went into trucks. Once the emissions laws kicked in, they had to find a different engine. 

GM's next couple of engines would also slot in right around this part of our list. The LMM engine that immediately succeeded the LBZ made 365 horsepower, and the one after that, the LML, could make 397 horsepower. It wouldn't be until the L5P that GM saw a major uptick in horsepower, but we'll talk about that later. GM's 2000s diesel engines were surprisingly strong.

Yes, you read that correctly. At one point, BMW actually made a quad-turbo diesel engine. It's only natural that such a strange creation would make its way onto a list like this. The engine was known as the BMW B57, and, as with most engines, there were a few variants. It's also one of the more modern engines on the list. BMW started putting it in cars in 2016, and it actually did well enough to leave it in the lineup for a number of years. 

The most powerful version of the B57 was the B57D30S0, which produced 394 horsepower and 561 lb-ft of torque. BMW also included a 48-volt mild hybrid starter generator to reduce turbo lag. It worked, and despite its weird quad-turbo setup, the engine is considered reasonably reliable. It's also fairly fuel efficient, achieving roughly 5.5 liters per 100 km, which loosely translates to around 42 MPG. Since multiple variants of this engine exist, there is a long list of cars in which it was installed. For the B57D30S0, which was the only version with quad-turbo, the models included the G11, G30, G05, G06, and G07. 

The story of the B57 is a tale of multiple engines. BMW used the quad-turbo version until the pandemic hit in 2020 and then ceased production. However, the twin-turbo B57D30T0 and the single-turbo B57D30O0 are still largely in use today in about a half dozen models each. Maybe they'll bring back the quad-turbo someday.

The Mack E7 is mostly for commercial use and is one of the best American-made diesel engines ever. It's also one of the oldest. It was introduced to the market in 1989 and has since been used in a variety of applications. They include semi-trucks, tractors, farm equipment, mining equipment, and basically anything else that can use a diesel engine as a power source. Mack made 16 variants of this engine by 1999 and, in total, produced the engine for around 20 years. 

Since there are so many variants from so long ago, it's tough to pin down the most powerful ones. However, there are examples that go up to 454 horsepower, which is very respectable given its age, and especially given that it's a four-cycle inline six and not something larger like a V8. In case you're curious, that 454 horsepower engine could output a monstrous 1,660 lb-ft of torque, so while the horsepower figures seem modest, the torque was incredible. 

New engines have replaced this engine, and they have higher horsepower. However, at 454 horsepower, the E7 is one of the strongest older diesel engines that we could find, and we felt it was worthy of a mention. Mack undoubtedly makes some of the strongest engines in its industry.

The Cummins 6.7-liter turbo diesel is the current champion of the Cummins lineup. It came to life in 2007 and is still made to this day. Like every other diesel engine maker, Cummins had to come up with something new to counter the emissions standards coming into effect in 2007. Cummins isn't known for releasing new engines very often. The ISBe's predecessor, the 5.9-liter ISB, lived from 1998 to 2007, and its predecessor lasted for 10 years before that. That makes this 6.7-liter turbo diesel the longest-running of Cummins' modern engines at 18 years and counting. 

Much like the Mack E7, Cummins farms out its engines to a lot of industries, but the strongest one we found made 420 horsepower and 1,075 lb-ft of torque. This particular engine is most commonly found in Ram trucks, namely the Ram 2500 (and higher), as recently as the 2025 model year. With its powerful diesel engine, the Ram 2500 can tow up to 20,000 pounds with a 4,000-pound payload capacity. That is a little over 2,000 pounds more than it can tow with the optional 6.4-liter Hemi V8.

Cummins doesn't appear to be stopping this train anytime soon. There is no word on a fresh new diesel coming down the line. Instead, Cummins seems content with iterating and improving its current engine. It makes sense. It's one of the strongest consumer-oriented diesels on the market, so there's no reason to change it up too much right now. 

We promised we would get to GM's L5P later, and now here it is. This is GM's most modern turbo diesel as of 2025. GM brought this 6.6-liter V8 diesel engine into existence in 2017. Back then, the engine was capable of 445 horsepower and 910 lb-ft of torque, which is exceptionally good for a pickup engine. GM did some sort of voodoo because its towing capacity was a staggering 35,500 pounds, second only to Ford in the tow ratings. GM made that version of the engine until 2023. 

From 2023 onward, a revision to the engine bumped up its numbers pretty dramatically to 470 horsepower and 975 lb-ft of torque. It's not quite as much as the Cummins, but nearly 1,000 lb-ft is still quite powerful. Much like the prior engines, these are mostly made for the larger trucks in GM's lineup, including the Silverado HD and Sierra HD. The bump in horsepower and torque allows properly equipped models to tow up to 36,000 pounds, which is simply incredible. 

For the time being, GM seems content with this engine, and it is currently equipped in 2025 models of the Silverado HD and Sierra HD. Should GM decide to make another diesel, it'll likely outperform this one, but as it stands, GM's main competitors are either a little weaker or a little stronger, putting GM in a pretty good spot. 

The Audi 6.0L V12 TDI is the final engine on this list to go into a car. Everything after this is for truck use only. This one also has quite the pedigree. It's been to the 24 Hours at Le Mans, an event that Audi has been dominating since the turn of the century, with 13 wins in the top class since the year 2000. Audi also puts it in its cars and SUVs for the sake of extravagance, since there is no reasonable cause to put a V12 engine into anything designed to get groceries or take the kids to school. Audi made this engine from 2009 to 2012.

Let's start with the power figures. The Audi V12 TDI gets up to 493 horsepower and 737 lb-ft of torque, making it one of the strongest consumer-oriented diesel engines ever. The only consumer vehicle to ever have it was the Q7, and all of those come with all-wheel drive. Compared to many of the diesels on this list, this thing chugs fuel at around 21 MPG combined with as low as 16 MPG in the city. Audi has stashed this thing in its Q7, an SUV that can achieve 0 to 60 MPH in under 5.5 seconds. Its theoretical top speed is 171 MPH. 

Audi deserves some credit for its diesel engines. The automaker was the first to win a 24 Hours at Le Mans with a diesel engine, and the V12 was born out of that success. However, in a Q7, you won't be taking it to the track.

Ford is among the leaders when it comes to powerful diesel engines meant for pickup trucks. Like GM, the brand has a history of some pretty epic diesels. Ford teamed up with another company — in this case, Navistar — to make some of its best diesel engines, including a 7.3-liter monster that put out a pretty excellent 225 horsepower in the 1990s. Ford would go on to make the 6.0-liter Power Stroke in 2003, which upped the ante to 325 horsepower, and then the 6.4-liter Power Stroke upped it again to 350 horsepower. 

GM's engines were doing better in the power department, and Ford decided to fix that with the 6.7-liter Power Stroke. The regular version makes a very impressive 475 horsepower and 1,050 lb-ft of torque, putting it more or less on par with GM and Cummins. However, the high-output variant brings it to 500 horsepower and 1,200 lb-ft of torque, which are both class-leading as of 2025. This allows Ford to also claim ownership in the tow capacity ratings for standard pickup trucks since the Power Stroke-equipped Ford F-450 can tow up to 40,000 pounds, topping the Silverado by 4,000 pounds. 

With those kinds of numbers, Ford can afford to sit on its laurels a bit since the competition is close but still behind in this regard. Discounting obviously stronger engines like those for semis, tractors, and modified engines, we were unable to find a production diesel stronger than Ford's HO Power Stroke. 

Now that we're done with consumer vehicles, let's shift over to commercial vehicles. Semi-trucks are known for having some of the strongest engines on the planet, which makes sense because they have to carry a lot of cargo over long distances. It wouldn't be fair to include all of them on this list because we've already done that. The weakest engine on that list is stronger than even the Ford 6.7-liter Power Stroke, starting with the Mack MP8 at 505 horsepower. There are also semi-diesel engines that have over 600 and 700 horsepower. 

So, we'll skip over those and talk about one of the strongest semi-truck diesel engines, the Weichai WP17H. This monster of a motor can get up to 800 horsepower and an astounding 2,766 lb-ft of torque. Weichai makes a few versions of this engine for things like mining dump trucks and silage harvesters, which shows that this engine is truly for the most hardcore work imaginable. 

Weichai wins the horsepower battle for now, but the torque winner is the Volvo D17. It boasts 780 horsepower and 2,803 lb-ft of torque. Between the two, it's virtually a toss-up as to which one is more powerful. In short, semi-truck engines put consumer-oriented diesels to shame, and by a fairly hefty margin. 

Finally, we come to the upper echelon of diesel engine horsepower. We generally stray away from modified engines in these types of lists, but the results for modified diesel engines were so completely otherworldly that we had to share them. Builders take a base engine and modify it to kingdom come, resulting in a diesel engine that will quite literally belch black smoke into the air like a 1920s cartoon coal train. This trend has gone back decades, with modders making 500 horsepower diesel engines in the 1980s and '90s, which is double what production diesels were getting back then.

These days, it gets even more ludicrous. It's not terribly uncommon to see 1,500 horsepower modified diesels in the wild, pulling off 9-second quarter-mile runs at the local drag strip. It's ridiculous, especially when you consider that some of them are running 3.0-liter diesels. In any case, the strongest diesel engine rating we could find belongs to Justin Zeigler and his 6.7-liter Cummins engine. When Zeigler put his truck on the dyno, it returned a figure of 3,336 horsepower and 3,642 lb-ft of torque. You read that correctly. 

Now, for context, that is three times as much horsepower as Dodge's legendary 7.0-liter V8 Hellephant engine and more than double the 8.0-liter W16 found in the 2024 Bugatti Chiron Super Sport, which is one of the most powerful engines in production today. For further context, Zeigler's engine can run an 1/8th mile in 4.99 seconds. The aforementioned Bugatti? An estimated 6.2 seconds. Case closed.