The Best Diesel Engines: Top 10 Of All-Time

The Most Revered Oil-Burners Ever Assembled

From the farm to the highway, construction equipment to gen-sets, and emergency vehicles to the trucks we drive every day, diesels have built—and continue to build—America. Even beyond our borders, in every mechanized blue-collar segment of the world, you’ll find a diesel in charge of the lion’s share of the workload. And although it goes without saying that all engine manufacturers strive to turn out the best product possible for every application, some power plants are simply better than others. Be it due to their durability, mechanical simplicity, or horsepower potential, these oil-burners are a cut above the rest—and we have 10 of the best diesels ever concocted to tell you about in the pages that follow.

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Many of our choices hearken back to the good old days, before the emissions crunch had completely taken hold and acronyms like EGR, DPF, and SCR had yet to complicate and ultimately cause so many of the reliability issues we’re familiar with today. Names like Cummins, International, Caterpillar, Detroit, John Deere, GM, and Mack all made the list, and the engines we’ve selected represent some of the finest examples of compression-ignition on the planet. Even with most of them now out of production, they remain celebrated and treasured. Without further ado, and in no particular order, we give you “the list”.

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International DT466

DW-2105-ENGINE-02 — Whether you know it or not, you’ve spent time around International’s DT466. School buses, box trucks, farm tractors, small bulldozers, and dozens of other applications have been powered by this legendary I-6. The largest of IH’s 400 series engines, the DT466 was the big brother to the 414 and 436 ci tractor engines, which all shared the same block. Its deep-skirt cast-iron crankcase housed an induction-hardened, forged-steel crankshaft with seven main bearings, utilized ductile-iron wet cylinder liners, and featured a 4.30-inch bore with a torque-happy 5.35-inch stroke.

DW-2105-ENGINE-03 — Thanks to a robust rotating assembly and six head bolts per cylinder being part of its mechanical makeup, the DT466 can withstand a lot of abuse in stock form. According to Hypermax Engineering, a big name in the world of tractor pulling, the iconic IH engine will handle 1,200 hp before the factory head gasket becomes a concern—and up to that point you can add all the fuel and air you want without worrying about hard-part upgrades of any kind.

DW-2105-ENGINE-04 — Aside from its anvil-like bottom end, simple 2-valve cylinder head, mechanical injection, and in-frame rebuildable design making it a favorite in the medium duty truck world, the DT466 found a natural home in tractor pulling also. Today, decades after discovering the limits of the factory components, replica blocks, billet cranks, stronger rods, and solid heads—combined with Sigma injection pumps, triple-feed injectors, and multiple turbochargers—DT466-based power plants can withstand 300-psi of boost and turn out more than 4,000 hp.

6BT Cummins

DW-2105-ENGINE-05 — Not only did the B-series 5.9L Cummins, the 6BT, revolutionize the pickup truck segment, it made it possible for a magazine like this to exist. Without it, the diesel industry wouldn’t have exploded the way it did and Diesel World might not have even been created. That’s how instrumental the 5.9L Cummins was in the expansion of the diesel marketplace. The 12-valve Cummins brought an I-6 design, direct-injection technology, and turbocharging to the ¾-ton and larger truck segment when it arrived in the summer of ’88, and Ford and GM have arguably been playing catch-up with the Chrysler/Cummins alliance ever since.

DW-2105-ENGINE-06 — One look at the 6BT’s connecting rods and you start to see why this overbuilt inline-six was capable of lasting a million miles, or surviving four-digit horsepower. Each forged-steel I-beam rod gets its own rod bearing journal (each one separated by a main bearing journal) and sports a 1.57-inch diameter floating wrist pin on the small end. When treated to shot peening, micro-polishing, and ARP rod bolts, these rods can live at 1,400-hp and more than 2,000 lb-ft of torque. The forged-steel and induction-hardened crankshaft is secured via 14mm main cap bolts, while the cylinder head employs six bolts per cylinder in its attachment to the cast-iron block.

DW-2105-ENGINE-08 — Though the 6.7L Cummins block, with the added strength that comes with its Siamese cylinder bores, is the favored crankcase for high-horsepower at the present time, the 5.9L block is still a viable option all the way up to 1,400-1,500 hp. Granted, the 5.9L’s threshold for horsepower is lower than that in street applications, but we’ve seen more than our fair share of them in the 1,100 to 1,200hp range.

DW-2105-ENGINE-07 — Simple yet proven, the 6BT Cummins’ crossflow, 12-valve cylinder head was cast from gray iron. However, its induction-hardened valve seats and ductile iron intake and exhaust valve rockers (not the common stamped steel type) suggest that it was built for the long-haul. In the world of diesel motorsports, the 12-valve head (and its aftermarket variants) is the weapon of choice. When treated to extensive porting (via CNC and/or by hand) and oversize valves, it can flow more than 300 cfm per cylinder (vs. 140-150 cfm stock).

3406 CAT

DW-2105-ENGINE-09 — There is no denying this engine’s presence in the Class 8 world, as thousands of over-the-road trucks still rely on it to propel them all over America in a trouble-free manner. It’s the legendary 3406 from Caterpillar and it’s a big reason why legions of truck owners swear by CAT power. Available in A, B, C, and eventually the coveted E model, the 3406 featured a bore of 5.40-inches, a stroke of 6.50-inches, and displaced 893 cubic inches (14.6L). Depending on the model, horsepower ratings ranged from 375-hp to 465-hp, with the highest factory torque output checking in at 1,850 lb-ft.

DW-2105-ENGINE-10 — As mentioned, the most revered 3406 carries an “E” at the end. While the 3406A and 3406B were fully mechanical engines (and the 3406C was a mix of both mechanical and electronics), the 3406E marked the point in time when CAT had mastered and then released a fully electronic unit injection system (circa 1993). Being full-on, electronically controlled meant that the engine control module (ECM) could be recalibrated, and when the right aftermarket reflash was uploaded some impressive horsepower gains were on the table. This hot-rod nature of the 3406E helped develop what became a cult-like following, where 550 and 600hp files were commonplace.

DW-2105-ENGINE-11 — In mega-horsepower, competition settings such as the 20,000-pound semi category in sled pulling, many drivers choose to campaign a 3406. This was the case for both Jerry and Jeremy Walker, a championship father and son duo that ran ragged edge versions in their semi’s, one a Peterbilt named “Two of a Kind” and the other an International coined “Down ‘N Out.” Both engines displaced more than 1,000 ci, each one being fed air via a massive single turbo with an inlet larger than 5-inches.

7.3L Power Stroke

DW-2105-ENGINE-12 — It’s not going to win any horsepower accolades or turn over happily in frigid conditions, but the 7.3L Power Stroke will never let you down. The largest diesel engine ever offered in the pickup segment, the Navistar-produced, 444 ci V-8 featured a 4.11-inch bore, a 4.18-inch stroke, and packed 210 horsepower and 425 lb-ft of torque when it debuted in mid-1994. Avant-garde for its day, the 7.3L Power Stroke featured hydraulically actuated electronically controlled unit injector technology (HEUI), an injection system developed by Caterpillar and leased to International to meet the coming emission standards. Direct injected and specifically designed around the use of a turbocharger, it was also Ford’s first serious answer to 5.9L Cummins-powered Dodge Rams.

DW-2105-ENGINE-13 — A forged-steel crankshaft, forged-steel connecting rods (although powdered-metal units were introduced after 2000), and direct-injection, cast-aluminum pistons with plasma-coated top piston rings speak to the 7.3L’s robust simplicity. The cast-iron heads featured two valves per cylinder but six head bolts per cylinder (with sharing). The valvetrain operated according to a single camshaft in the conventional V-8 location within the block, and hydraulic lifters meant no periodic adjustment of the valves was necessary.

DW-2105-ENGINE-15 — Low engine speed, big iron components, and (let’s face it) a lack of power is a great recipe for making any diesel last—and the 7.3L had all three of those characteristics working in its favor. After all, the most powerful version of the 7.3L produced kicked out just 275 horsepower and 525 lb-ft of torque (available beginning in ’01, but only in conjunction with the six-speed manual), a far cry from the 1,000 lb-ft diesels sitting on dealer lots at the present time.

DW-2105-ENGINE-14 — To mechanical injection fans, common-rail owners, diesel outsiders, or those whose first exposure to hydraulically actuated fueling came in the form of the 6.0L Power Stroke, the HEUI injection system is sometimes frowned upon. However, the system’s injectors, high-pressure oil pump, and injection pressure regulator were very reliable in the 7.3L application. Properly maintained injectors are virtually guaranteed to last 200,000 miles before requiring an overhaul, and many sets last well beyond that. Even today, 19 years after production of the 7.3L ceased, repair shops are still pulling original injectors (units equipped with black O-rings) out of engines.

Cummins 855 Big Cam

DW-2105-ENGINE-16 — Designed to adhere to the new emission standards set forth in the Clean Air Act of 1976, Cummins released the 855 Big Cam. It soon proved to arguably be the most fuel efficient, most durable, and most powerful engine available in a Class 8 truck—thereby owning the road for most of the late 1970s and early 1980s. The 855 ci (14.0L) Big Cam I (four versions would be available in all) possessed a 5.50-inch bore, a 5.98-inch stroke, and most versions were available with power ratings that ranged from 250 to 400 hp. However, some 855 Big Cam engines were rated as high as 605 hp in gen-set form.

DW-2105-ENGINE-17 — The first three renditions of the 855 Big Cam (i.e. Big Cam I, II, and III) utilized Cummins’ PT (pressure-time) fuel system, which allowed for mechanically variable timing. Electronics entered the fold in 1985 aboard the Big Cam IV, but the Big Cam IV was soon replaced with the N14. Improvements throughout the Big Cam’s production run included the demand-flow cooling system and pulse exhaust manifold that debuted on the Big Cam II engine in 1979, a pressed-steel oil pan and Holset HT3B turbocharger added for the Big Cam III in 1983, and a revised cylinder head and pulse exhaust manifold for the Big Cam IV in 1985.

John Deere 50 Series 6-619

DW-2105-ENGINE-18 — It would be criminal to overlook the 619 ci 50 Series John Deere engine after having listed the International DT466 as one of the best diesel power plants ever. After all, exotic tractor pulling versions of the green I-6 have been duking it out (and often winning) against DT466-based mills for years now. Down on the farm, you can typically find the 619 swapped in place of a 5010, 5020, or 6030’s original 531 ci engine. Out on the track, the 619-based ‘Deeres tend to dominate in classes where their big cubic inches are allowed to run free.

DW-2105-ENGINE-20 — From the factory, the 619 ci (10.0L) 50 series John Deere features a 5.125-inch bore, a 5.00-inch stroke, cylinder liners, and six head bolts per cylinder—a perfect foundation for both longevity and/or huge horsepower. One of its most favorable attributes is the fact that its oil pump is crank-driven rather than cam-driven. Excessive cam wear was common on the 30 and 40 series engines that preceded the 50 series, and many owners upgraded to the 50 series when major mechanical failures or problems were encountered for this very reason.

DW-2105-ENGINE-19 — In the wild world of Pro Stock tractors, you don’t exactly see factory-based 619 John Deeres under the side shields. The block may be stock or a factory replica, but within it lies a billet crank, rods, pistons, a girdle, and a 1-inch thick deck plate holding it all together up top. In addition, most 619’s are brought up to the class maximum of 680 cubes to compete at the maximum displacement allowed. From there, a billet Sigma pump and billet cylinder head (some capable of flowing as much as 500 cfm) is combined with a turbocharger sporting a 5.5-inch or larger inducer. Rumor has it that the current crop of Pro Stock John Deere engines can spin 6,000 rpm and belt out as much as 4,200 hp on the dyno. Talk about Big League stuff!

Mack E7

DW-2105-ENGINE-21 — Any diesel produced in the 1980s but that survived a major emissions crunch before being retired is worthy of mention. Mack’s E7 is one such engine. The E7 line, which consisted of 16 different versions of the same I-6, was released in 1988 and underwent several changes (even becoming the E7 E-Tech) during its 20-plus year production run. To many, the 728 ci (12.0L) E7 epitomizes the manufacturer’s bulldog logo to a “T.” Its horsepower ratings ranged from 250 to 460 hp but, in true Mack-like fashion, earth-rotating torque was generated right off idle. The torquiest version of the E7 (the 460hp model) turned out 1,660 lb-ft of torque at 1,200 rpm. Also typical of a Mack mill, the 12.0L E7 produced torque numbers that rivaled what larger engines from competing manufacturers were producing at the time.

DW-2105-ENGINE-22 — The first E7’s were fully mechanical, but electronics would infiltrate the works beginning in the early 1990s. Mack’s initial (and partial) electronic control over its fuel system was coined V-MAC (vehicle management and control), which added a rack actuator, rack position sensor, and a timing reference sensor to the Bosch inline pump. Mack’s Econovance system also brought variable mechanical timing into the picture to help custom-tailor fuel delivery to the end user’s needs. In 1998, the E7 received Mack’s electronic unit pump (EUP) system, a pump that was cam-driven. By 2003, EGR was making its way onto the revamped 12 liter engine, and the million-mile engine slowly lost its longtime luster.

Detroit Diesel 60 Series

DW-2105-ENGINE-23 — Without the Series 60 engine line, Detroit Diesel may have continued to lose market share in the 1980s and eventually folded up. Thankfully, that didn’t happen. When other engine manufacturers were just beginning to recognize that electronic control was the wave of the future, Detroit developed the 677 ci 11.1L and 778 ci 12.7L from scratch and hit a homerun right off the bat. Each engine’s unit injection system was completely electronic and performed flawlessly, as did the rest of the engine. In fact, the initial overhaul interval recommendations of 500,000 miles were changed to 750,000 miles soon after these engines were released.

DW-2105-ENGINE-24 — It’s been documented that Detroit Diesel, owned at the time by GM, reached out to John Deere in the mid 1980s for help in reviving its dying engine program. A short time later, the 60 series appeared on the scene, which virtually solved every issue the previous 50 series power plants had before it. Later on in 2001, Detroit set its sights on the larger engine market with the release of its 858 ci 14.0L engine. This version, possessing a long 6.62-inch stroke (and a 5.24-inch bore), was capable of producing 1,650 lb-ft of torque at 1,200 rpm, along with 515 hp at 1,800 rpm.

KTA Cummins

DW-2105-ENGINE-25 — Though pictured in gen-set trim here, the KTA Cummins was the largest Class 8 engine ever found on America’s highways. A square engine, its 6.25-inch bore and stroke made for 1,150 cubic inches (19.0L) of displacement, and although its original intent was never to power over-the-road trucks, the KTA made its way into them nevertheless. Single turbo Class 8 versions sported a single turbo and could crank out 600 hp—a very big number back in the late 1970s and 1980s. Peak torque from the factory checked in at 1,650 lb-ft, but it’s rumored that the KTA had to be fueled conservatively at low rpm to limit torque (that 1,650 lb-ft wasn’t available until 1,600 rpm), thereby increasing the lifespan of whatever transmission was bolted up behind it (usually an eight or 13-speed Eaton Fuller).

DW-2105-ENGINE-26 — Like the 855 Big Cam engines of the era, the KTA used Cummins’ PT (pressure-time) fuel system. With little more than fueling and turbo upgrades, the KTA could achieve four-digit horsepower and still go to work every day of the week. As for high-horsepower, truck-pulling applications, the 1,150 ci Cummins dominated the ranks of hot-rod type semi classes for years, in large part thanks to its solid foundation and obvious displacement advantage over other Class 8 engines. Now for the best part…There was also a KTTA, the double T meaning twin-turbo. The KTTA was primarily reserved for gen-sets and industrial-type use.

6.6L Duramax

DW-2105-ENGINE-27 — It’s the only engine with aluminum heads and one of just two V-8’s on our list, but it’s certainly no less deserving of being here. When the 6.6L Duramax (RPO code LB7) blasted onto the scene in the summer of 2000 for ’01 model year GM HD trucks, it boasted the highest horsepower and torque any diesel pickup ever had before—but that wasn’t all. Beyond its class-leading 300 hp and 520 lb-ft of torque, the Duramax brought common-rail injection, the quietest and cleanest diesel engine operation anyone had ever heard or seen, and the aforementioned aluminum cylinder heads to the pickup truck segment.

DW-2105-ENGINE-28 — The LB7 Duramax’s 4340 forged-steel crankshaft was heat-treated, forged-steel cracked cap rods were employed, and the cylinder walls’ combustion areas were induction-hardened (something GM’s rivals weren’t doing). Looking back, the 6.6L Duramax’s same basic architecture has survived more than 20 years of production now, and with very few design alterations. It still utilizes a deep-skirt, cast-iron block (where both the Power Stroke and even Cummins have since gone to CGI), and the same bore, stroke, and valvetrain arrangement. While it’s one of the more complex diesels on our list, there is no arguing with its ability to go the distance. We’ve seen several 500,000-mile candidates, as well as an LMM version with more than 750,000 on the ticker.

FREQUENTLY ASKED QUESTIONS

What are the advantages of diesel engines over petrol engines?

Diesel engines stand out over petrol engines for several compelling reasons:

Durability and Long Lifespan

One of the most significant advantages of diesel engines is their durability. These engines are primarily gear-driven, meaning critical components like oil and water pumps are less likely to fail quickly compared to their belt-driven counterparts. The reliance on gears, which are easier to maintain and repair, extends the engine’s lifespan significantly.

Efficiency Under Tough Conditions

Designed to handle extreme conditions, diesel engines are often used in heavy-duty applications worldwide. This means they are built to endure high stress and perform reliably in challenging environments, whether in construction, shipping, or agriculture.

Superior Combustion Process

Diesel engines utilize a unique combustion process where fuel is injected into the combustion chamber at high pressure. This method, known as spontaneous combustion, allows for efficient fuel utilization and reduces wear and tear on the engine parts, contributing to their longevity.

Fewer Maintenance Requirements

Thanks to their robust construction and efficient design, diesel engines require less frequent maintenance. When maintenance is necessary, it generally involves less complex repairs that can be managed more easily than those required for petrol engines.

Greater Fuel Economy

Diesel engines are known for their superior fuel efficiency. They extract more energy from the same volume of fuel compared to petrol engines, making them a cost-effective choice for long-distance travel and heavy use.

High Torque Generation

Diesel engines produce more torque than petrol engines at lower RPMs. This high torque is beneficial for tasks that require heavy pulling power, such as towing and hauling loads, making diesel engines the preferred choice for trucks and large vehicles.

By comprehensively understanding these advantages, it becomes clear why diesel engines are often the go-to option for demanding applications and long-term reliability.

Why do diesel engines last longer than petrol engines?

Understanding the Longevity of Diesel Engines

When comparing diesel engines to petrol engines, one significant advantage is their remarkable lifespan. But what makes diesel engines more durable?

Robust Design

Diesel engines are built with a gear-driven architecture, which enhances their reliability. Gears, unlike other mechanical components, are straightforward to maintain and repair. They also maintain their timing more effectively, reducing wear and tear.

Heavy-Duty Parts

Another contributing factor is the utilization of heavy-duty parts. Diesel engines often power machinery and vehicles in harsh environments worldwide. These engines are designed to withstand extreme conditions, contributing to their longevity.

Efficient Combustion

The combustion process in diesel engines differs significantly from that in petrol engines. Diesel engines use a method known as spontaneous combustion. In this process, diesel fuel is injected into the combustion chamber at high pressure and preheated. This efficient combustion process means that diesel engines don’t strain as much, leading to extended durability.

Gear-Driven Pumps

Many diesel engines incorporate gear-driven oil and water pumps, which wear out more slowly than belt-driven counterparts. This slower rate of failure means that essential components of the engine are maintained in better condition over a longer period.

Summary

In essence, the durability of diesel engines comes down to their robust design, the use of heavy-duty parts, efficient combustion, and gear-driven components. These attributes make diesel engines a reliable choice for long-term use, especially in challenging environments.

What are the best diesel trucks for long-lasting performance and easy maintenance?

Top Diesel Trucks for Longevity and Simplified Maintenance

When on the hunt for a used truck that can stand the test of time and require minimal upkeep, certain models stand out due to their robust build and lasting performance. Below are some top picks that deliver durability and ease of maintenance.

Dodge Ram HD

Known for its rugged reliability, the Dodge Ram HD series is a solid choice for those seeking a truck that can handle tough conditions. The 2003-2004 models are especially noteworthy, featuring a 5.9L Cummins engine that can tow up to 12,000 lbs. This model is revered as a reliable workhorse that won’t leave you stranded.

Dodge W250

Not many people are familiar with the Dodge W250, but it’s a hidden gem in the diesel truck world. First introduced in 1989, this model includes a Cummins 6-cylinder engine enhanced with an intercooler and overdrive transmission, making it nearly indestructible. Although tracking down a W250 might be challenging, its simple and durable design makes it easy to maintain once acquired.

1999 Ford Super Duty

The 1999 Ford Super Duty is a classic example of Ford’s engineering excellence. Equipped with a durable Power Stroke engine, this truck includes a factory intercooler, forged steel connecting rods, and a high-pressure oil pump. It’s also highly modifiable, with abundant aftermarket parts that can boost its horsepower beyond 500, making it both practical and powerful.

2008 Ford F-250

Choosing a single Ford F-250 model is difficult due to their consistent reliability, but the 2008 edition stands out. Featuring a 6.4L Power Stroke turbocharged engine, this model is a favorite for its modifiability. The stock engine produces 350 horsepower and 650 lb-ft of torque, and with some tuning and simple upgrades, you can easily push it beyond 600 horsepower. Its robust design and popularity in the aftermarket make it a must-have for truck enthusiasts.

Key Features for Long-Lasting Performance and Maintenance

Engine Durability: Look for models with well-regarded engines like the Cummins or Power Stroke.
Modifiability: Trucks that support easy modifications provide long-term usability.
Component Quality: Features such as factory intercoolers and forged steel connecting rods indicate a strong build.
Parts Availability: Choose models with readily available aftermarket parts for easier upgrades and repairs.
Towing Capacity: High towing capacities often indicate a stronger, more durable truck.

Choosing a diesel truck from these recommendations ensures you get a vehicle that’s built to last and won’t require constant, costly maintenance. Consider these models for their proven track record and robust performance.

What are some of the best diesel trucks of all time that can be purchased second-hand?

Best Diesel Trucks of All Time to Buy Second-Hand

Searching for a Reliable Used Diesel Truck?

When it comes to picking a second-hand diesel truck, you want performance, durability, and reliability. Here are some top-notch diesel trucks that hold their own even years after hitting the market.

Iconic American Workhorse: Dodge Ram HD

Known for its ruggedness, the Dodge Ram HD is a steadfast choice. The model years between 2003-2004 are particularly outstanding, featuring a robust 5.9L Cummins engine capable of towing up to 12,000 lbs. If you’re looking for a truck that can handle heavy lifting and rough terrain, this is a solid option.

The Underrated Gem: Dodge W250

Many may not recognize the Dodge W250, but this model is a sleeper hit among diesel trucks. Introduced in 1989 with a Cummins 6-cylinder engine, it gained a reputation for durability, thanks to upgrades like an intercooler and an overdrive transmission. While finding one might be a challenge, its reliability makes it worth the hunt.

The Modifiable Powerhouse: 1999 Ford Super Duty

Ford’s Super Duty trucks are legends in their own right, and the 1999 model stands out. Equipped with a sturdy power stroke engine, factory intercooler, forged steel conrods, and a high-pressure oil pump, this truck promises robust performance. An added bonus is its ease of modification, with abundant aftermarket parts to boost its horsepower well beyond standard.

The Versatile Beast: 2008 Ford F-250

The 2008 Ford F-250 is a favorite among truck enthusiasts, thanks to its 6.4L power stroke turbocharged engine. Straight out of the factory, it delivers 650 lb-ft of torque and 350 HP. However, it shines in its modifiability; with simple tweaks like a new intake and exhaust, you can push its power beyond 600 HP. This model is a top pick for anyone looking to maximize both utility and performance.

Conclusion

These second-hand diesel trucks offer a blend of reliability, power, and modifiability. Whether you need a workhorse for heavy lifting or a versatile beast that you can customize, any of these models will serve you well for years to come.

What are the features and capabilities of the Dodge Ram HD diesel truck?

Features and Capabilities of the Dodge Ram HD Diesel Truck

The Dodge Ram HD diesel truck is renowned for its rugged reliability and outstanding performance. This workhorse is engineered to tackle a wide range of challenges, making it a favorite among truck enthusiasts and professionals alike.

Engine Power

Equipped with a robust 5.9L Cummins engine, this truck delivers remarkable power, enabling it to tow up to 12,000 lbs. Whether you’re hauling heavy equipment or a trailer, the Dodge Ram HD handles the job with ease and efficiency.

Durability and Build

The truck’s design emphasizes durability. Constructed to endure tough conditions, it features a resilient frame that stands up to the rigors of daily use. This reliability ensures you won’t be left stranded, no matter where your journey takes you.

Versatility

There are numerous models and configurations available, catering to various needs and preferences. The 2003-2004 editions, in particular, have garnered praise for their exceptional build quality and performance.

Off-Road Capabilities

Thanks to its advanced suspension system and powerful drivetrain, the Dodge Ram HD can navigate rough terrain smoothly. This makes it an ideal choice for both off-road adventures and demanding work environments.

Load Capacity

Aside from its impressive towing capacity, the truck also boasts a substantial payload capacity. This means you can carry more gear, materials, or tools without compromising on performance.

Comfort and Technology

Inside, the cabin offers a blend of comfort and technology. Features such as ergonomic seats, intuitive controls, and modern infotainment systems ensure a pleasant driving experience, even on long hauls.

If you’re in the market for a truck that combines power, durability, and versatility, the Dodge Ram HD diesel truck stands out as a top contender.

Why are diesel engines preferred for trucks and pickups in tough conditions?

Diesel engines are also used in applications around the world where conditions are tough and there’s a reliance on heavy-duty parts to withstand these tough conditions. This is why they are preferred for trucks and pickups operating in harsh environments—they offer unmatched reliability and durability.

And although it goes without saying that all engine manufacturers strive to turn out the best product possible for every application, some power plants are simply better than others. Be it due to their durability, mechanical simplicity, or horsepower potential, these oil-burners are a cut above the rest—and we have 10 of the best diesels ever concocted to tell you about in the pages that follow.

Why is diesel considered more durable and reliable for heavy-duty applications?

Why Diesel Engines Are Durable and Reliable

Diesel engines rely on spontaneous combustion, where diesel fuel is injected into the combustion chamber at high pressure. This high-pressure injection, combined with preheating the diesel before injection, ensures efficient combustion. This type of combustion process is less stringent on engine intervals, making for a long-lasting, durable engine.

All engine manufacturers strive to turn out the best product possible for every application, but some power plants are simply better than others. Be it due to their durability, mechanical simplicity, or horsepower potential, these oil-burners are a cut above the rest.

Key Factors Contributing to Diesel Engine Durability:

Spontaneous Combustion: The process itself is inherently efficient and less stressful on engine components.
Preheated Fuel: Ensures thorough combustion, reducing wear and tear.
Less Stringent Intervals: The combustion process allows for longer intervals between maintenance, contributing to longevity.

We have 10 of the best diesels ever concocted to tell you about in the pages that follow.

What common issues do diesel engines face, and how do they impact performance and reliability?

Diesel engines, while known for durability and efficiency, do encounter some common issues that can affect their performance and reliability.

Supercharger and Bearing Failures

A frequent problem with diesel engines is the premature failure of shaft bearings within the supercharger. This issue often leads to a decline in power and inconsistent engine performance. To mitigate this, some manufacturers have transitioned from using ceramic bearings to more robust steel ball bearings, enhancing longevity.

EGR Valve Clogs

The Exhaust Gas Recirculation (EGR) valve is another component that can cause headaches for diesel engine owners. This valve tends to get clogged, particularly in vehicles that predominantly navigate city traffic. A clogged EGR valve can lead to uneven performance and increased emissions, noticeable through excessive smoke.

Fuel Injection System Complications

Diesel engines, like those using Bosch injection systems, are sometimes plagued by issues in the fuel injection process. Fortunately, many of the malfunctioning components are repairable, which helps keep repair costs manageable. However, addressing these issues promptly is crucial to maintain engine reliability.

DPF Blockages

City driving can also lead to the blockage of Diesel Particulate Filters (DPF). These filters are essential for reducing harmful emissions, and when clogged, they not only impair engine efficiency but can also cause significant performance drops.

By understanding these common diesel engine problems, vehicle owners can take proactive measures in maintenance, ensuring their engines remain reliable and performant. Regular checks and timely repairs are key to mitigating these issues.

What criteria were used to select the top diesel engines for this list?

Be it due to their durability, mechanical simplicity, or horsepower potential, these oil-burners are a cut above the rest—and we have 10 of the best diesels ever concocted to tell you about in the pages that follow.

Selecting these top diesel engines wasn’t an easy feat. Much like a lively debate among friends, our team engaged in spirited discussions, weighing the merits of each contender. It’s akin to asking a parent to choose their favorite child—each engine has its own unique strengths and stories.

Our Criteria:

Durability:These engines are built to last, surviving the toughest conditions.
Mechanical Simplicity:Engines that embody elegant engineering without unnecessary complexity.
Horsepower Potential:Those powerhouses that deliver impressive performance.

We know some of you will wholeheartedly agree with our choices, nodding along as you read. Others might feel we missed the mark entirely. Both perspectives are valid, and that’s the beauty of this subject—passion fuels discussion. We invite you to share your own lists and join in the conversation.

So, dive into the pages ahead and explore these remarkable diesel engines that have left their mark on automotive history.

What are some of the greatest diesel engines ever made?

The Most Revered Oil-Burners Ever Assembled

The Pioneering Powerhouse

Engine Type: Four-cycle, six-cylinder, inline
Displacement: 359 ci (5.9L)
Maximum Power: 325 hp
Maximum Torque: 610 lb-ft

This engine paved the way for respectability in diesel pickups, offering a torque that feels like it could relocate skyscrapers.

The Road Warrior

Engine Type: Four-cycle, six-cylinder, inline
Displacement: 466 ci (7.6L)
Governed Speed: 2,600 rpm

A favorite among fleet managers, this engine is known for its efficiency and the ability to be rebuilt right in the truck’s chassis, making it a hero on the highways.

The Colossal Contender

Engine Type: Two-cycle, 14-cylinder, inline
Displacement: 1,556,002 ci (25,480L)
Maximum Power: 108,920 hp

Used in massive ships, this engine boasts power that could energize small nations, proving size does matter.

The Racing Beast

Engine Type: Four-cycle, six-cylinder, inline
Displacement: 732 ci (12.0L)
Maximum Power: 1,400 hp

A true factory hot rod, this engine propels racing rigs to incredible speeds, showcasing power and indestructibility.

The Innovator

Engine Type: Four-cycle, V-8
Displacement: 403 ci (6.6L)
Maximum Power: 360 hp

This engine marked a turning point with its introduction and continues to outrun competitors in diesel power wars.

The People’s Choice

Engine Type: Four-cycle, V-8
Displacement: 444 ci (7.3L)

Introducing diesel power to a wider audience, this engine sparked a race for horsepower and torque among major manufacturers.

The Pleasure Craft Marvel

Engine Type: Four-cycle, V-16
Displacement: 3,967 ci

Masterfully crafted with precision, this engine delivers immense horsepower, turning any boat into a powerful vessel.

The European Wonder

Engine Type: Four-cycle, V-10
Displacement: 300 ci (5.0L)

With small displacement but mighty output, this engine exemplifies European mastery of turbodiesels, driving SUVs with surprising agility.

The Technological Trailblazer

Engine Type: Four-cycle, six-cylinder, inline

The first heavy-duty diesel with electronic controls, setting the stage for the current boom in diesel upgrades.

The Original

Engine Type: Two-stroke, single cylinder
Displacement: 1,200 ci (60.0L)

The engine that birthed it all, introducing biodiesel before it became a trend and forever changing engine design.

These mechanical marvels not only highlight the innovation and engineering prowess of their creators but also underscore the profound impact diesel engines have had on industries worldwide.

What advancements did the Series 60 engine introduce to heavy-duty diesel engines?

Without the Series 60 engine line, Detroit Diesel may have continued to lose market share in the 1980s and eventually folded up. Thankfully, that didn’t happen. When other engine manufacturers were just beginning to recognize that electronic control was the wave of the future, Detroit developed the 677 ci 11.1L and 778 ci 12.7L from scratch and hit a homerun right off the bat.

The Series 60 was groundbreaking as the first fully integrated heavy-duty diesel with electronic controls. This innovation set the standard back in 1987, paving the way for modern electronically controlled diesel power upgrades that are commonplace today. Its unit injection system was completely electronic and performed flawlessly, as did the rest of the engine.

In fact, the initial overhaul interval recommendations of 500,000 miles were changed to 750,000 miles soon after these engines were released. While the Series 60 may not have the iconic sound of the old Series 53, 71, and 92 two-stroke diesels, its technological advancements and reliability ensured its place in the annals of diesel engineering.

What impact did the introduction of the Duramax engine have on the diesel marketplace?

It’s the only engine with aluminum heads and one of just two V-8’s on our list, but it’s certainly no less deserving of being here. When the 6.6L Duramax (RPO code LB7) blasted onto the scene in the summer of 2000 for the ’01 model year GM HD trucks, it boasted the highest horsepower and torque any diesel pickup ever had before—but that wasn’t all. Beyond its class-leading 300 hp and 520 lb-ft of torque, the Duramax brought common-rail injection, the quietest and cleanest diesel engine operation anyone had ever heard or seen, and the aforementioned aluminum cylinder heads to the pickup truck segment.

The arrival of the Duramax was a game-changer in the diesel marketplace. After years of trailing behind its competitors, GM finally struck back with this powerhouse, marking a strategic pivot in its diesel strategy. This robust entry didn’t just match the competition; it set a new benchmark, outpacing the other major players.

Key Features and Impact

Revolutionary Design: The aluminum heads were a first in the segment, contributing to both performance and efficiency.
Power and Performance: With 300 hp and 520 lb-ft of torque, it redefined what diesel pickups were capable of.
Technological Advancements: The integration of common-rail injection technology resulted in a quieter and cleaner engine, transforming consumer expectations.

In the competitive landscape of diesel power, the Duramax’s introduction was a bold statement. It wasn’t just about joining the race—it was about leading it. The engine’s capability to outrun its rivals in power and sophistication underscored a new era for diesel engines in the automotive industry. As a result, the Duramax didn’t just enhance GM’s standing; it reshaped the standards of diesel performance across the board.

Why is the Power Stroke engine notable in the history of diesel engines in the U.S. Market?

With over 2 million sales of this engine in the US alone, the Power Stroke tops the charts as the most successful diesel engine that has ever existed. Used in trucks and pickups, the Power Stroke is strapped to almost anything that requires a long-lasting, robust, and powerful engine.

But what makes the Power Stroke truly notable in the history of diesel engines? It did more than just sell well; it revolutionized the market by introducing countless truck owners to the wonders of diesel grunt. This engine wasn’t just a bestseller; it was a trailblazer that fueled a competitive horsepower and torque race among major automakers.

Reliable and readily available, the Power Stroke made diesel ownership mainstream, shifting perceptions and setting new standards for what diesel engines could achieve. It wasn’t just an engine; it was a movement that transformed the landscape of the U.S. diesel market.

How is the B-Series Cummins engine significant in the history of diesel engines?

Not only did the B-series 5.9L Cummins, the 6BT, revolutionize the pickup truck segment, it made it possible for a magazine like this to exist. Without it, the diesel industry wouldn’t have exploded the way it did, and Diesel Worldmight not have even been created. That’s how instrumental the 5.9L Cummins was in the expansion of the diesel marketplace.

The significance of the B-Series Cummins in diesel history cannot be overstated. It wasn’t just another engine—it was the first to bring genuine respectability to diesel in pickup trucks. This respectability turned skeptics into believers and paved the way for diesel’s mainstream acceptance in the automotive world.

The 12-valve Cummins brought an I-6 design, direct-injection technology, and turbocharging to the ¾-ton and larger truck segment when it arrived in the summer of ’88, and Ford and GM have arguably been playing catch-up with the Chrysler/Cummins alliance ever since. One look at the 6BT’s connecting rods, and you start to see why this overbuilt inline-six was capable of lasting a million miles or surviving four-digit horsepower. Each forged-steel I-beam rod gets its own rod bearing journal (each one separated by a main bearing journal) and sports a 1.57-inch diameter floating wrist pin on the small end. When treated to shot peening, micro-polishing, and ARP rod bolts, these rods can live at 1,400-hp and more than 2,000 lb-ft of torque. The forged-steel and induction-hardened crankshaft is secured via 14mm main cap bolts, while the cylinder head employs six bolts per cylinder in its attachment to the cast-iron block.

With enough torque to relocate skyscrapers, the B-Series Cummins has remained fantastic over the years. Its durability and power have not only influenced the design and engineering of future diesel engines but have also set a standard that many have tried to emulate. This legacy is a testament to its groundbreaking role in the diesel engine’s storied history.

How did the Caterpillar engine perform in racing big rigs?

Rumor has it that the current crop of Pro Stock John Deere engines can spin 6,000 rpm and belt out as much as 4,200 hp on the dyno. Talk about Big League stuff!

But the real magic happens on the track. These engines are not just about raw numbers—they’re built for performance that translates into real-world success. With this kind of power, you can expect these beasts to launch a racing rig down the track with blistering speed. Imagine a machine that can effortlessly hit top speeds, transforming those impressive dyno stats into championship-winning performance.

It’s not just about power; it’s about consistency and durability. These engines are engineered to withstand the grueling demands of competitive racing, ensuring they deliver race after race. Whether it’s the roar of the engine or the thrill of the acceleration, these machines are designed for those who crave the adrenaline and prestige of the racing world.