Here Are The Duramax Years To Avoid
Duramax by Kevauto - CC-BY-SA-4.0
The Duramax V8 engine is a 6.6-liter Diesel engine produced by DMAX, a combined effort between General Motors and Isuzu.
The Duramax debuted in 2001 as the successor to the 6.2L and 6.5L Detroit engines. It proved to be a powerful and great contender in the light diesel market. Over the years, the engine has gone through several upgrades and improvements to ensure GMC and Chevrolet pickup trucks perform better than their competition.
In this post, we’ll tell you which Duramax years to avoid and which one to go for if you’re looking to buy a used Chevy or GMC truck. This information is based on the number of complaints filed by users concerning the different model years. Let’s dive in.
Quick Answer: Avoid Duramax Year Models 2001-2010
The Duramax has a long history. We recommend avoiding any GM vehicle equipped with the 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, and 2010 Duramax engines. In short, the newer model years show improved performance.
The first engine was the 6.6L Duramax LB7 used in the 2001 – 2004 Chevrolet Kodiak, Chevrolet Silverado, GMC Topkick, and GMC Sierra HD. It was the simplest in the lineup because it did not have a diesel particulate filter (DPF) or exhaust gas recirculation (EGR). These came later.
The Duramax LLY took over from the LB7 in 2004. It came in the Chevrolet Silverado, Hummer H1 Alpha, and the GMC Sierra until 2005. GM then introduced the Duramax LBZ for the 2006 – 2007 Chevrolet Silverado HD, Chevrolet Kodiak, Chevrolet Express, GMC Sierra, GMC Topkick, and GMC Savanna.
The last engine on our list that we also recommend avoiding is the Duramax LMM which debuted in 2007 – 2010. It is fitted in the Chevrolet Kodiak, Silverado HD, Express, GMC Topkick, Sierra HD, and Savanna. Keep reading to find out the specific issues that plague these Duramax model years.
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Which Duramax Year Modes Are Safe to Buy Used?
According to GM Authority, up to 11 types of Duramax engines have been produced globally since 2001. They include a wide range of eight, six, and four-cylinder options in V or inline (I) configurations. This means that there are plenty of engine choices to pick from.
Earlier Duramax engines were characterized by a couple of inevitable problems that eventually cost owners in repairs. If you’re looking for an engine that won’t trouble you much, we recommend the following Duramax year models:
- 2010 – 2017 Duramax LGH
- 2011 – 2016 Duramax LML
- 2011 – 2021 Duramax XLD25
- 2012 – 2021 Duramax XLD28
- 2014 – 2021 Duramax LWN
- 2017 – 2021 Duramax L5P
- 2019 – 2021 Duramax LM2
The Duramax engine received significant changes in 2011 to meet the new emissions regulations. Despite it being more complicated than its predecessors, it is more reliable. The safest Duramax model years you can buy are the models produced from 2011 to 2021.
These include the Duramax LGH, Duramax LML, Duramax XLD25, Duramax XLD28, Duramax LWN, Duramax L5P, and Duramax LM2. These engines go a step further to provide better emissions thanks to a diesel exhaust fluid/urea injection feature. An after-treatment system also allows owners to increase fuel economy using exhaust after-treatments.
The only problem you may experience in these engines is weak tie rods that may go bad when drag racing, off-roading, or sled-pulling. The exhaust after-treatment system/diesel particulate filter also comes with a failure point that can cause problems.
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Which Duramax Years to Avoid?
If you’re looking for fuel economy, reliability, comfort, and power, there are plenty of Duramax engines that you can choose from. This is especially true if you’re in the market for a Chevy Silverado or GMC Sierra younger than ten years old.
Thus, you must know which Duramax years to avoid. We recommend staying away from GM trucks that have the following engines:
- 2001 – 2004 Duramax LB7
- 2004 – 2005 Duramax LLY
- 2006 – 2007 Duramax LBZ
- 2007 – 2012 Duramax LMM
According to Driving Line, if you have a Chevy Kodiak, Chevy Silverado, GMC Sierra HD, or GMC Topkick with the Duramax LB77, it is virtually inevitable that you’ll experience a problem with the fuel injection system. This is especially the case if the previous owner did not follow GM’s protocol to have the injectors replaced under warranty.
As for the Duramax LLY engine fitted in the 2004 – 2005 Chevrolet Silverado, Hummer H1, and GMC Sierra HD, the most common problems that owners experience include overheating when towing and blown head gaskets.
The LBZ is perhaps one of the most desired Duramax engines. It addressed the overheating and blown gasket issues that plague the LLY. However, we recommend staying away from it due to pistons that crack at higher horsepower. Some users also complained about cab corners and rocker panels that rust faster in northern regions due to high humidity and salt.
The Duramax LMM took over from the LBZ in 2007 and was fitted in the Chevrolet Silverado HD, Kodiak, Express, GMC Topkick, Savanna, and Sierra HD until 2010. Like its predecessor, it also suffers from cracked pistons at higher horsepower. The diesel particulate filter also comes with a failure point.
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Common Duramax Diesel Engine Problems
Every engine has its share of quirks, and the Duramax V8 engine is no exception. Here are some of the most common problems across all Duramax years.
- Fuel injector failure: Common with the LB7 Duramax engines, the premature injector failure caused so many headaches for owners. Apparently, the fuel injectors were prone to fuel leaks, leading to fuel dilution. GMC had to recall the issue for this design flaw.
- Water pump failure: The LB7 and LLY engines had problems with faulty water pumps. With a defective water pump, the engine will likely overheat. GMC released a more prominent, redesigned water pump to address this issue.
- Turbocharger oil ingestion: This issue affected the 6.6L Duramax LB7, LLY, LBZ, LMM, and LML engines, so it’s pretty prevalent. According to experts, the PCV design of the Duramax vents excess pressure into the intake. This causes the engine oil to be introduced into the turbocharger.
- Glow plug failure: The LLY and later the LBZ struggled with glow plug failure. The culprit was determined to be the faulty glow plug modules. If left unattended, a catastrophic engine failure is highly likely. Once again, GMC had to issue a recall for this issue.
What’s the Life Expectancy of Duramax Diesel Engines?
While the Duramax engine is truly a marvel of engineering, one of the most common questions about it is its life expectancy. Thankfully, Duramax diesel engines are reliable by default and can last you for hundreds of thousands of miles, especially with proper care and maintenance.
Many Duramax vehicles are still on the road today and still work like new despite passing 100,000 miles. According to many owners, Duramax engines can reach 200,000 with little to no issues. With proper maintenance, Duramax engines can run north of 300k-400k miles. People at the Duramax Forums claimed their vehicles had reached 300,000 and even 400,000 miles with just the stock engine. One user even commented on pushing 535,000 miles on his LB7, which is mind-blowing.
The average driver can expect about 200k-300k miles before needing any major repairs. Of course, these numbers will depend on how you use your vehicle and the amount of maintenance you give it. At the end of the day, it’s fair to say that Duramax engines are reliable and long-lasting.
What’s the Life Expectancy of Duramax Diesel Engines?
While the Duramax engine is truly a marvel of engineering, one of the most common questions about it is its life expectancy. Thankfully, Duramax diesel engines are reliable by default and can last you for hundreds of thousands of miles, especially with proper care and maintenance.
Many Duramax vehicles are still on the road today and still work like new despite passing 100,000 miles. According to many owners, Duramax engines can reach 200,000 with little to no issues. With proper maintenance, Duramax engines can run north of 300k-400k miles. People at the Duramax Forums claimed their vehicles had reached 300,000 and even 400,000 miles with just the stock engine. One user even commented on pushing 535,000 miles on his LB7, which is mind-blowing.
The average driver can expect about 200k-300k miles before needing any major repairs. Of course, these numbers will depend on how you use your vehicle and the amount of maintenance you give it. At the end of the day, it’s fair to say that Duramax engines are reliable and long-lasting.
FAQs: Duramax Engine Years To Avoid
Q: Which Duramax diesel engine years should be avoided?
A: According to the guide, it is recommended that you avoid any GM vehicle equipped with Duramax engines from 2001 to 2010. These years are known for various issues that could impact the engine’s performance and reliability.
Q: What were the common problems with the LB7 engine?
A: The LB7 Duramax engine, used from 2001 to 2004, is particularly notorious for injector failures. These issues were so prevalent that they led to a significant recall. Owners faced problems like fuel dilution and were often required to replace injectors prematurely, which could be costly.
Q: Why is the LBZ Duramax engine considered desirable despite being on the avoid list?
A: The LBZ Duramax engine, produced between 2006 and 2007, is often sought after by enthusiasts for its solid performance and lack of certain emissions control features in later models. However, it’s advised to be cautious with the LBZ Duramax due to potential issues like cracked pistons at higher horsepower and susceptibility to rust, especially in harsh climates.
Q: Are newer Duramax engines more reliable than the older model years?
A: Yes, Duramax engines produced after 2010, especially those from 2011 onwards, have shown improvements in reliability and performance. They incorporate advanced technology to meet emissions standards and improve fuel efficiency, making them a safer bet for those seeking a dependable diesel engine.
The Easiest Way to Buy a Reliable Duramax in Your Area
Looking for a GMC or Chevrolet with a Duramax engine in your area? The best way to find a reliable Duramax engine is by downloading the free CoPilot car shopping app. We provide a list of every dealership that’s close to where you are. This makes it easy for you to find a heavy-duty truck that meets your needs.
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