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2004-2006 6.6L LLY Duramax Maintenance Guide

In a few, short years the Duramax made a name for itself. It was more powerful, capable, and reliable than GM’s previous trucks. When the LLY Duramax replaced the LB7, it offered several improvements. It also posted improvements in tow capacity, horsepower, and torque. Like the LB7, the LLY Duramax can last a very long time if taken care of properly. That means you need to follow the proper service schedule and use the right parts. If you maintain your LLY by yourself, you can also save yourself hundreds of dollars. What if you’re not familiar with these trucks though? We take the guess work out of the equation. All you need to do is follow our comprehensive 6.6L LLY Duramax Maintenance Guide. It’ll give you the know-how to successfully maintain your LLY Duramax by yourself.

6.6L LLY Duramax Service Schedule

How Often Should I Service My LLY Duramax?

How often you should service your 6.6L LLY Duramax is going to depend on how much you use it, and what you use it for. Excessive idling, heavy towing, or off-roading will result in the need to perform service more regularly. You should follow the severe service schedule. If you tow mostly light loads or use the truck for mostly commuting, you should use the normal operating conditions service schedule. If you don’t hit the mileage requirements, check your owner’s manual for the specific time period in which you should change your fluids and filters. Change your LLY’s engine oil and filter at least once every 6 months and your fuel filters once a year. Keep an eye on your air filter and change it as needed. If you’re in very dusty areas you will likely need to change it sooner.

Normal Operating Conditions

Severe Operating Conditions

Keep in mind there are other vehicle features you need to check and possibly replace. Every service you should be checking and rotating your tires. You also need to inspect all suspension and steering components and make sure they are properly lubricated or greased. Front end failures are one of the most common LLY Duramax problems.

What Do I Need to Check Every Time I Service my Truck?

Here’s a little checklist of things you need to do check time your perform maintenance on your LLY Duramax.

• Check all areas and components holding fluid or oil for leaks
• Check tires for signs of leaks, damage, dry rot, or uneven wear.
• Inspect All suspension and steering components for signs of play or torn boots/seals etc…
• Check your air filter to see if it needs to be changed.
• Check transmission dipstick and smell the fluid. See the quality of fluid or if it smells burnt.
• Check all suspension/steering and other truck components that need regular lubrication or greasing. If needed, add lubricant or grease.

LLY Duramax Fluid/Oil Capacity Guide

Best 6.6L LLY Duramax Fluids, Oil, and Filters

Commonly Used LLY Duramax Service Parts

LLY Duramax Steering/Suspension Replacement Parts

Learn More About 2004-2006 GM Diesel Trucks

Want to learn more than just LLY Duramax Maintenance information? Click on one of the links below or in the side bar!

• LLY Duramax Specifications
• 9 Best LLY Duramax Performance Upgrades
• 5 Most Common LLY Duramax Problems