How Many Miles Will a 6.6 Duramax Last [+Maintenance Tips]

The First Duramax diesel engine is manufactured in 2001 to be used in pickup trucks.

Since then the manufacturing unit and popularity of Duramax diesel engine is increasing day by day.

Duramax engine had some issues at the beginning but later most of the issues have been solved by the manufacturer.

Presently, Duramax is reliable and one of the top diesel engines in America.

But, how many miles will a 6.6L Duramax engine last?

Well, the life expectancy of a Duramax 6.6 is around 2,00000 miles without any major repair.

But it can last up to 4,00000 if properly maintained.

So, the exact life expectancy of a Duramax depends on maintenance.

Properly maintained and poorly maintained vehicles’ life expectancy is completely different.

What is the Life Expectancy of a Duramax Diesel Engine?

The life expectancy of a Duramax diesel engine is about 2,00000 miles to 4,00000 miles.

However, with proper maintenance and care, it is not uncommon for them to last much longer.

Many people report getting 4,00000 miles or more out of their Duramax engine.

Proper driving and regular servicing are important factors for Duramax’s long-lasting.

How Many Miles Will a 6.6 Duramax Last?

6.6 Duramax engine is considered to be a reliable and durable engine.

Some problems like injection pumps and emissions systems in the previous model have been solved in 6.6 Duramax.

Though, Duramax 6.6 is sold with a warranty of 1,00000 miles.

If someone asks how many miles can you get out of a Duramax?

Well, Duramax 6.6 engines last over 2,00000 miles without any major repairs or diagnoses.

Even some owners have reported that their Duramax lasts over 4,00000 miles.

If the Duramax is maintained properly and serviced promptly, it easily crosses this life expectancy.

Currently, it is used by a huge number of users, and its popularity is increasing daily.

GM gives a rating to engines based on their durability and wears, and they give a 95% rating at 200,000 miles.

Duramax’s longevity depends on the maintenance of the vehicle.

If you don’t maintain your vehicle properly it won’t last long.

On the other hand, a properly maintained Duramax will last longer than the average lifespan.

Here are 18 tips for the Duramax to last longer.

18 Duramax Maintenance Tips

6.6 Duramax Engine

Follow these 18 maintenance guides to enhance the life expectancy of your Duramax diesel engine.

By following these tips, your Duramax engine will last up to 4,00000 miles.

Let’s begin-

  1. Make sure you change the engine oil and filter regularly
  2. Use suitable oil and oil filters
  3. To refill the diesel exhaust fluid, open the fuel DEF door (some vehicles need to open the hood to find the DEF door), remove the blue cap, and pour the DEF using a funnel
  4. Now, wait for the fluid level to update on the DIC
  5. Wipe away any spills
  6. Place the cap back and close the fuel door
  7. Change the fuel filter; follow the owner’s manual first because the location of the fuel filter varies from vehicle to vehicle
  8. Before changing the filter, ensure your engine is turned off and the vehicle brake is applied
  9. Before changing the fuel filter, drain water from the filter
  10. Withdraw the filter element cap
  11. Withdraw the old filter element & O-ring
  12. Place the new O-ring around the cap and lubricate it
  13. Install the new filter element into the housing
  14. Place the cap back and tighten it
  15. Prime the fuel filter
  16. Reset the fuel filter life
  17. Have the engine serviced regularly
  18. And make sure you drive the vehicle regularly to keep the engine in good condition

The process may vary depending on your vehicle.

So, always follow the specification in your owner’s manual.

If you face any problems performing the procedures, we recommend taking the vehicle to a service center.

This video will help you.

What to Look for When Buying a Used Duramax?

It is important to focus on some major factors before buying a used Duramax.

This will save you money and provide you with a good quality Duramax.

So, let’s check the factors-

Checking Cooling Pressure

Check the cooling pressure of a Duramax engine before purchasing it.

The cooling pressure should be between 15 to 25 psi.

Checking the Engine Oil

Checking the Engine Oil

It’s important to check the engine oil to ensure it is properly lubricated.

Checking Engine Codes

Engine codes will tell you if there are any problems with the engine.

If the engine codes are not checked, the engine could have problems, and that can cause the truck to break down.

Injector Balance Rate

Check the injector balance rate to ensure it is compatible with your engine.

Check the Drivability

Make sure the vehicle can drive smoothly and without any issues.

Also, check the condition of the engine and transmission to avoid any potential problems.

Check the 4WD System

Check it by engaging the 4WD and then driving the truck in a straight line.

If the truck pulls to one side, the 4WD system is not working properly.

Also, put the truck in 4WD and then a drive-up hill.

The 4WD system is not working accurately if the truck slips or slides.

Listen for a Hissing Noise

The Duramax is a great truck engine but is not without problems.

It has a common problem with the turbo.

There is a problem if there is any hissing noise in the turbo.

Check the Brake Pad Wear

Check the Brake Pad Wear

You can check the brake pad by looking at the brake pad’s thickness.

Exhaust Noise

Exhaust noise is an important thing to consider before buying a used Duramax.

Inspect the exhaust system for any leak or damage.

Cummins Vs Duramax, Which One is Better?

Two famous diesel engines in America are Cummins and Duramax.

Comparing them is subjective and varies from person to person.

Cummins engine is leading in torque, but in terms of horsepower, Duramax is one step ahead.

Let’s discuss them separately.


Considering the history and experience of Cummins, the Cummins engine has over 100 years of experience.

The engine came to the production line in 1919.

The Chrysler Corporation put the engine in their Ram trucks in 1989.

On the other hand, GMs started producing Duramax in 2001.

It is just 20 years of experience.

In the case of history and experience, Cummins is in a leading position.

The first Cummins diesel engine in Ram trucks was the 5.9L 6-cylinder that provided 400 lb-ft of torque.

At that time, it held the top position over all other engines by offering huge torque.

In 2007, 6.7L replaced its older version 5.9L Cummins diesel engine.

However, many parts are the same as their older parts.

This model produces 850 to 1000 lb-ft of torque, depending on the truck.

6.7L Ram Cummins diesel produces 400 hp.


The Duramax engine was produced by GM 20 years ago in 2001.

The first generation came out in 2001 and offered 520 lb-ft of torque.

2018 GM 6.6L L5P Duramax engine’s current generation produces 910 lb-ft of torque.

This model offers 445 horsepower also.

The Ultimate Decision Between Duramax vs Cummins

From the above discussion, we can say that Duramax leads with high hp, and Cummins leads with torque.

But the final consideration, with high hp and torque output, Duramax competes with Cummins very well.

Moreover, durability and performance keep Duramax slightly ahead.

Is a Duramax Worth It?

A Duramax is worth it if you are looking for a reliable engine.

A Duramax engine is a diesel engine used in GMC and Chevrolet trucks.

It is a high-performance engine known for its towing and hauling capabilities.

Duramax diesel offers great gas mileage than gas engines.

Its pulling and hauling capacity are also higher than gas engines.

Some users may have a small problem with the higher cost of diesel than gas.

Apart from this diesel engine has many advantages.

As we mentioned, it is also a very reliable engine, which is why many people believe it is worth the investment.

How long will the Duramax last compared to the Powerstroke?

Duramax vs Powerstroke are two well-known engine titans. Both engines have some differences in torque output, horsepower, and towing capacity. But when we discuss about longevity, they are both at the top of the list.

The Powerstroke manufacturer Ford claims that their engine can last 300,000 to 500,000 miles, depending on the maintenance and driving conditions.

On the other hand, Duramax’s manufacturer General Motors claimed that their Duramax can last up to 500,000 miles. The Duramax and Powerstroke both have impressive lifespan on paper.

But as a professional mechanic, I can say that changing air filters and oil alone won’t get you over the half-million mark.

It also requires a balancing act of miles, maintenance, and a dash of luck. So the longevity of Duramax or Powerstroke is dependent not only on the company’s claims but also on you.

What is the issue with the 2024 Duramax?

2024 Duramax is a powerful engine, but it has some problems just like any other mechanical part.

Common problems with 2024 Duramax are:

1. Fuel Injector Issue

The 2024 Duramax has fuel injector issues. GM issued a recall for 2024 Silverado HD and Sierra HD models that equipped with Duramax engine.

Incorrect Electronic Control Module (ECM) adjustments cause improper fuel injector circulation issues.

2. Turbocharger Issue

Some owners reported about premature turbocharger failure issues in 2024 Duramax engine. This problem is responsible for reducing power and requires costly repairs.

Symptoms of 2024 Duramax Turbocharger Problems:

  • Reduce power
  • Excessive smoke
  • Unusual whistling noises.


How long do Duramax diesels last?

The LB7 original Duramax model is very popular among diesel enthusiasts.

The reason for this popularity is its lack of emission control parts.

The Duramax diesel should last over 400k miles with proper care.

How many miles will a 2008 6.6 Duramax last?

Without proper maintenance, it will last around 3,0000 miles.

But with proper maintenance, it will last up to 4,00000 miles.

How many miles will a Duramax Last?

Duramax diesel engines have been known to last over 400k miles with proper care and maintenance.

The Duramax diesel engine is a high-performance engine used in various applications, including heavy-duty trucks, buses, and RVs.

It is famous for its high torque output and fuel efficiency.

The engine is also very reliable, making it a popular choice for many truck and vehicle owners.

How many miles will an LBZ Duramax last?

The LBZ is also one of the most famous Duramax engines.

Its additional performance and hp make it more popular.

The lasting of LBZ Duramax depends on how you treat it.

LBZ Duramax lasts over 4,00000 miles if you maintain it properly and change fluids and filters regularly.

How long will a LLY Duramax last?

The LLY Duramax is also reliable like other Duramax engines.

The LLY Duramax will last as long as the truck lasts.

The engine is designed to last the lifetime of the truck.

A well maintains LLY Duramax can last over 400k miles.

How many miles on Duramax before rebuild?

Duramax is a very reliable engine.

Choosing Duramax as a companion for long trips is a good decision.

With Duramax, you can drive over 2,00000 miles without any major issues.

But with maintenance, it will last up to 4,00000 miles.

This is one of the reasons for its popularity.

Is the Duramax diesel a good engine?

Duramax diesel is considered to be the best post-emission engine.

Duramax diesel is one of the main engines in General Motors (GM) trucks.

The engine is very much durable and reliable.

The Duramax diesel has plenty on the road today, and they are still running like new after approaching over 3,50000 miles.

For pulling and towing, Duramax diesel is the best choice.

Duramax diesel is used in large trucks and has a powerful trailer.

Overall, Duramax’s engine performance is very good, and these features replace it in the good engine category.


Now you know the life expectancy of your 6.6 Duramax.

Maintenance is the main key to longevity.

So, don’t neglect to maintain your vehicle unless you want a short life expectancy from your vehicle.

Read more:

Leave a Comment