Fans Say These Are The 3 Most Reliable Duramax V8 Engines

When it comes to pickup trucks, most enthusiasts take a hardline stance. You're either a Ford fan, a Ram fan, or a Chevy fan. There doesn't tend to be a lot of compromise or love lost between the three groups, and each one will defend their chosen brand with enthusiasm that verges on fanaticism. For Chevy lovers, the Duramax engine is the pinnacle of non-commercial diesel performance. But while GM fans generally all agree that the Duramax motor is superior to its rivals, they don't consider all Duramax iterations to be equal.

Since its debut in 2001, the eight-cylinder Duramax motor has seen six major variations. A seventh variation technically exists in the form of the LGH. But in reality, the LGH is basically a detuned version of the LML engine that GM produced between 2011 and 2016, and the only differences are additional emissions controls installed for specific markets. In terms of the best Duramax V8 engine, most fans agree that the LBZ, which GM produced between 2006 and 2007, is the most reliable and versatile of the lineup. However, the LBZ isn't the only Duramax iteration that fans hold in high regard.

The overwhelmingly top fan-rated Duramax engine is the LBZ. Produced between 2006 and 2007, the LBZ is beloved by enthusiasts due to its reputation for reliability and long-lasting power. One of the primary things that fans love about the LBZ is its lack of emissions control devices. But this isn't due to hatred of the environment. Instead, fans prize the LBZ because its lack of emissions devices makes it incredibly reliable. After 2007, GM began installing a series of emissions parts on the LBZ's Duramax successors. Unfortunately, these devices are notorious for failure, resulting in significantly less reliable performance. Because the LBZ does not include these devices, it has fewer known failure points and can be expected to outlast many of its successors.

The LBZ is also beloved for its modification potential. These engines are ripe for tuning and performance add-ons and, according to fans, are built to be more reliable and stronger than previous iterations. The LBZ can tolerate substantial modification and is capable of producing hundreds of horsepower — up to a point, that is. At around 600 horsepower, the LBZ's pistons are known to crack. However, to reach 600 horses in the LBZ, enthusiasts need to fork over upwards of $20,000, so the pistons shouldn't be an issue for most drivers.

The very first Duramax V8, to hit the market back in 2001, the LB7, does not include emissions control devices, which is one of the main reasons for its popularity and reliable reputation. This isn't because Duramax fans hate the environment but rather because they prize the reliability that comes with a more basic engine design free of emissions parts. The LB7 is also considered an excellent base for modification. It features an incredibly strong block and solid internals, allowing fans and enthusiasts to add performance parts and tune the engine without fear of compromising stock components.

The LB7 does have a weak point, though, in the form of its fuel injectors. The stock injectors failed so frequently that GM issued a special recall to replace the original injectors with more robust versions and extended the warranty to 200,000 miles or seven years, whichever comes first. While this means that LB7 engines are no longer covered under warranty, owners can swap modern Duramax injectors into their LB7, simultaneously resolving the injector problem and fortifying the older motor with contemporary parts.

Since 2017, the L5P has represented the eight-cylinder Duramax lineup and is quickly growing in popularity among fans. The newest Duramax engine — found in the Chevrolet Silverado HD and GMC Sierra HD — includes modern emissions control devices. But unlike previous Duramax generations, these parts are not known for causing failure in the L5P.

The L5P produces an impressive 445 horsepower and 910 pound-feet of torque. It features many modernized components to increase performance and power, including new cast aluminum heads, which create increased engine airflow, and a lift pump, which drastically reduces the pressure on the fuel pump and increases horsepower and reliability. Furthermore, the new Duramax features a state-of-the-art air intake system. This modern, patent-pending system draws cool air in through a hood scoop, drastically increasing the engine's performance under stressful conditions, like towing heavy loads up steep inclines.

Fans rave about the L5P's towing capacity and performance. And even though it's the newest Duramax on the market, the L5P is quickly developing a name for itself as a powerful and reliable motor and cementing its position on the list of top fan-rated Duramax V8 engines.