They're not all Toyota motors, either.
Car enthusiasts may enjoy tinkering with their engines from time to time, but the majority of car and truck owners see their vehicles as appliances to get to and from work. When a vehicle is an appliance, reliability is crucial, and while we've already dealt with the most reliable cars ever made, today we're highlighting the most reliable engines ever made.
It's important to note that there will probably be some engines we've missed, as there have been tens of thousands of motors built globally since the car was invented. It's also worth remembering that sometimes, reliable engines have been put in unreliable cars, which has tainted their legacy. And then there are ownership standards - even the most reliable engine will die if mistreated. Still, we've selected ten engines that have proven themselves reliable in a multitude of vehicles.
Sports cars sound like the least likely place to find a reliable engine, given that they get driven hard, placing more wear on the motor. But the Mk IV Toyota Supra disproved that with its 2JZ engine and variants thereof. This legendary 3.0-liter inline-six had a cast iron block and an aluminum head and was known to be absolutely bulletproof. Tuners have squeezed out close to 1,000 horsepower on stock internals, reliably so, and for those left stock, standard maintenance is all it needs to keep on clocking hundreds of thousands of miles.
The 1JZ also deserves mention - the 2.5-liter version of the JZ inline-six that spanned 17 years.
Outputs ranged from just 168 hp in naturally aspirated versions of these motors to thousands in highly tuned and built versions. But in almost all scenarios, the JZ was as bulletproof as they come.
You had to know there'd be a reliable Honda engine on this list, and it's none other than the ever-popular K-series. Launched in 2001, these dual overhead camshaft-equipped (DOHC) four-cylinder motors range in displacement from 2.0 to 2.4 liters and have served in a variety of Honda models from the early Civic Type R to the Integra, Accord, CR-V, Acura RDX, and so much more.
Available in both naturally aspirated and turbocharged forms, the latter have proven the most reliable and popular as an engine swap for car enthusiasts, with a high-rev ceiling and bulletproof engineering making them perfect for revvy performance builds where reliability is paramount. The K20 and K24 variants have proven most popular and have also been considered some of the better-sounding four-cylinder engines of their era, particularly early variants. And yes, the K-series has V-TEC, just like any good Honda engine should.
People can say what they want about American build quality, but we know how to build a proper small block V8. The General Motors LS family of small-block V8s has been around since 1997, spanning three generations, with a fourth due in the next few years. Used in everything from the Chevy Silverado to the Camaro, the LS has proven incredibly reliable and easy to maintain in almost every form.
Various displacements have been made available, from 4.8-liter versions (Vortec 4800 LR4) to 7.4-liter ones. Between these outer limits, there have also been 5.3-, 5.7-, 6.0-, 6.2-, 6.6-, and 7.0-liter versions, with outputs ranging from 255-755 hp depending on the model.
We're not going to pick just one as our favorite, though, as across the board, the LS has a reputation for reliability, with truck owners recording hundreds of thousands of miles of trouble-free motoring and tuners using the LS for easy, reliable power in just about every situation.
Toyota has a reputation for reliable motors, with the UZ family being one of the best. In the US, the GM LS may be the default V8 swap, but everywhere else in the world, the Toyota UZ is where it's at. This 90-degree V8 family started life in 1989 in the Lexus LS 400 - a legend in its own right - and remained in production until 2013. Its combination of power, reliability, and refinement saw it used in luxury sedans, minibuses, pickup trucks like the Tundra, and off-road SUVs like the Land Cruiser, Sequoia, and Lexus LX/GX.
Displacements offered included 4.0 liters in the 1UZ, 4.7 liters in the 2UZ, and 4.3 liters in the 3UZ, but the latter generation also included 4.5- and 5.0-liter racing variants used in the Japanese Super GT and Grand American Road Racing (Grand Am) series. Known to be extremely under-stressed, outputs ranged from 256-500 hp.
The UZ family was so reliable it was even used as the basis of a marine motor, while a twin-turbo derivative was used in aviation.
BMW and inline-sixes go together like baseball and hot dogs, but even among great BMW six-pots, the M50 stands out as a legend. Produced for only seven years from 1990-1996, it replaced the M20 when it launched in the E34 5 Series. Displacements ranged from 2.0- to 2.5 liters and power outputs from 148 to 189 horsepower. The M50 became the first BMW motor to use variable valve timing when it received a 1992 update that included single VANOS on the intake cam.
It also served as the foundation for the S50 used in the E36 M3, and its design was so mechanically sound that it inspired the next several generations of BMW six-cylinders. It wasn't just reliable in stock form, though, and its cast iron block is known for handling heavy doses of boost pressure in forced induction setups.
Another short-lived yet incredibly reliable motor was the Volkswagen ABF engine. This 2.0-liter 16-valve four-cylinder was produced from 1992-1999 and was a performance motor found in the Mk III Golf GTI and fourth-gen Passat in several markets. It was known as a rev-happy motor delivering 148 hp at 6,000 rpm and 133 lb-ft of torque at 4,800 rpm. It had a cast iron block and aluminum head with hydraulic lifters and fuel injection. While it is considered extremely reliable and is often used as a performance swap in early Volkswagen builds, parts are known to be pretty expensive, especially as they become scarcer. Common faults typically relate to ancillary sensors rather than the motor itself, with the throttle position sensor being a known problem.
Still, the ABF is known to happily reach 250,000 miles with aggressive driving with no major issues.
We've all heard tales of diesel-powered Mercedes taxis cresting 600,000 miles in Germany without their engines ever being opened. Those are more than just fairytales, though, with much of that reliability attributed to the OM617 engine family. Testament to its longevity, the OM617 five-cylinder diesel engine was produced from 1974 to 1991 as a 3.0-liter with a cast iron block and head and a chain-driven single overhead camshaft.
The OM617 is also considered a key factor in the reputation Mercedes built for reliability in the US in the 1980s, striking a perfect balance between power and reliability, two factors that diesel engines of the era weren't exactly well known for.
It evolved from the OM616 four-cylinder, itself a reliable motor, and debuted in 1974 on the W115 (an early predecessor to the E-Class) with just 79 hp and 127 lb-ft in naturally aspirated form. It was joined two years later by a turbo-diesel variant with 187 hp, which was dropped into the iconic Mercedes C111-IID concept, setting 16 world land speed records. A subsequent upgrade in 1978 pushed outputs to 227 hp, adding another nine records to the C111's resume.
This motor became the heart of the world's first turbodiesel production sedan, the North America-only W116 300SD.
The Ford straight-six is an icon in its own right, but the fourth-generation six introduced the Ford 300 engine, a 300 cubic inch/4.9-liter gasoline six-pot that was first offered in the 1965 F-Series pickup as a long-stroke version of the 240 six-cylinder. It produced 170 hp to start, although a change in power rating standards meant that number dropped to 114 hp (net) in 1978 when the motor became the base option in the F-Series. Throughout its life, it saw its power increase, first to 122 hp in the 1980s and then to 150 hp in 1987 when it switched to fuel injection.
The Ford 300 was used for everything from pickup trucks to dump trucks that weighed as much as 20,000 lbs, with heavy-duty upgrades like forged internals making them absolute workhorses. It saw use in tractors, wood chippers, water pumps, ski lifts, and UPS trucks, and even won the Baja 1000 three times in a truck piloted by Scott Donohue.
But in all applications, it was known for needing minimal maintenance, and forums are filled with dozens of accounts of the Ford 300 refusing to die, even when neglected, running low on oil, and not being maintained. It was considered by many as indestructible.
Production ended in 1996, and it has the honor of being the last inline-six gasoline engine in a Ford car or light truck in North America.
A reliable engine in one car is one thing, but a reliable engine ubiquitous across dozens of models is another entirely. The Chrysler Slant-Six was the latter, an inline-six engine canted at 30 degrees that was produced in various iterations for 41 years from 1959 to the turn of the millennium across 31 models. These included the Chrysler Cordoba, LeBaron, and Fifth Avenue; the Dodge Dart, Aspen, Challenger, and Charger; the Ram Van, Ram Pickup, and the Plymouth Barracuda, Belvedere, Duster, Gran Fury, and dozens more, earning it a reputation as an engine that could work in anything and never die, even in performance applications.
The Slant-Six was available in three primary configurations: 170, 198, and 225, all referring to the engine's displacement in cubic inches (2.8, 3.2, and 3.7 liters), but within these, there were a variety of versions with short blocks and tall blocks, different numbers of main bearings, and a plethora of other changes. However, the core design remained the same, and the motor was rigid, cooled itself well, and even lent itself to motorsport applications with some success.
Whether it had a cast iron or aluminum block (both materials were used), it was reliable all the same.
Yeah, it's another Toyota engine, but what can we say? Toyota knows how to make a reliable engine.
The GR engine family - not related to GR models that use the Gazoo Racing branding - spans eight different variants and multiple sub-variants, but the 2GR is the most widely renowned for its reliability. This is the 3.5-liter, 60-degree V6 produced from 2005 till today that you know and love from the Toyota Tacoma, Camry, Highlander, and Avalon, as well as the Lexus ES, GS, IS, RX, and various others. It was even used in the Lotus Evora and as a racing engine in the Toyota Corolla.
The 2GR-FSE variant has earned a spot on the Ward's 10 Best Engines list multiple times and is a favorite among fans who appreciate its reliability and robustness in any application.
Constructed with a die-cast aluminum block and an aluminum head, it's one of the most modern engines on this list and also one of the most powerful, with outputs ranging from 245-316 hp depending on application.
Because it's been used in so many models, all of which tend to be best-sellers, it's also proven itself globally and has an abundance of support should the worst happen.
We could've spent days of research and thousands more words to try and cover the most reliable engines out there but settled for the ten above. Still, some nearly made the cut that we feel deserve mention.