LB7 Duramax Maintenance Schedule, Fluid Specs, And Parts
2001-2004 Duramax Maintenance Schedule
The LB7 Duramax was incredibly impressive for its time. Over the years, we’ve found out just how reliable and capable the trucks are. That doesn’t mean they are flawless though. By following GM’s recommended LB7 Duramax Maintenance schedule and service intervals you can drastically reduce the amounts of problems you will encounter. Using OEM parts and filters from GM or ACDelco also have a big impact on keeping your truck out of the shop. Finding information on a truck from the early 2000s isn’t always easy though. It’s very likely your LB7 is missing it’s owner’s manual and diesel supplement. How then, do you know when to you need to service your truck and what parts you need to buy if you’re going to service it yourself? That’s easy, just follow our comprehensive guide to 6.6L LB7 Duramax Maintenance.

Our 6.6L LB7 Duramax Maintenance guide goes over everything you need to know to properly maintain these trucks. We give you service schedules for normal and severe use, fluid capacities, and a complete list of recommended filters, engine oils, and fluids to use. If you have a different type of Duramax, check out our other maintenance guides. We have comprehensive maintenance guides for the LLY, LBZ, LMM, LML, and L5P models.
How Often Do I need to Service My LB7 Duramax?
If you just bought an LB7 Duramax, I strongly recommend performing a thorough maintenance and covering all of your bases. You don’t know how the truck was driven or how well it was taken care of. Whenever I buy a truck, I replace all the fluids, filters, and engine oil as soon as possible. If you’ve owned the truck for a while, and you’re wondering when you should service your truck, take a look at our charts below.
Down below are two charts explaining what services need to be completed at certain intervals. There are two different maintenance intervals you can follow with your LB7 Duramax. Which one you follow depends on how you use your truck. Read the short paragraphs for each chart to determine if that is the proper LB7 Duramax maintenance schedule for you to follow.
Maintenance Intervals – Normal Conditions
The normal conditions maintenance scheduled should be followed by most people. If you use your truck mostly as just a daily driver, and don’t tow heavy loads frequently, this should be the maintenance interval you follow for your LB7.
Maintenance/Service | Miles | Kilometers |
Change Oil | 10,000 miles | 16,000 km |
Change Oil Filter | 10,000 miles | 16,000 km |
Change Fuel Filter | 15,000 miles | 24,000 km |
Replace Air Filter | Check At Every Oil Change; Replace when necessary. Consider replacing air filter every 30-45,000 miles. If you frequently drive in dusty conditions you may need to change your air filter more often. | 48,000 km- 72,000 km |
Flush Cooling System | 150,000 miles | 240,000 km |
Change Manual transmission fluid | No Interval Given; Consider servicing every 50-75,000 miles. | 80,000 km- 120,000 km |
Replace Automatic Transmission Fluid | 50,000 miles | 80,000 km |
Change External transmission filter | 50,000 miles | 80,000 km |
Change internal transmission filter | 50,000 miles | 80,000 km |
Replace Transfer Case Fluid | 50,000 miles | 80,000 km |
Replace Rear Differential Fluid | Not Provided; We Recommend changing fluid every 100,000 miles. If axle is submerged underwater, replace fluid ASAP. | See Left 160,000 km |
Replace Front Differential Fluid | Not Provided; We Recommend changing fluid every 100,000 miles. If axle is submerged under water, replace fluid ASAP. | See Left 160,000 km |
Maintenance Intervals – Severe Conditions
If you tow or idle frequently, you need to follow the severe conditions LB7 Maintenance schedule. This is especially important if you tow heavy loads. Heavy towing can take a big toll on your LB7 Duramax. You’ll need to complete common maintenance tasks like changing the oil and transmission fluid more frequently. If you are often in dirty or dusty conditions, keep an eye on your air filter. It will need to be changed more frequently too.
Maintenance/Service | Miles | Kilometers |
Change Oil | 5,000 miles | 8,000 km |
Replace Oil Filter | 5,000 miles | 8,000 km |
Change Fuel Filter | 15,000 miles | 24,000 km |
Replace Air Filter | As needed; check air filter at every oil change. Replace if necessary. We recommend 20-30,000 mile intervals if driving in dusty conditions. | 32,000 km- 48,000 km |
Flush Cooling System | 150,000 miles | 240,000 km |
Replace Automatic Transmission Fluid | 25,000 miles | 40,000 km |
Change Manual transmission fluid | No Interval Given; Consider servicing every 50-75,000 miles. | 80,000 km- 120,000 km |
Change External transmission filter | 25,000 miles | 40,000 km |
Replace internal transmission filter | 25,000 miles | 40,000 km |
Replace Transfer Case Fluid | 50,000 miles | 80,000 km |
Replace Rear Differential Fluid | Not Provided; We Recommend changing fluid every 100,000 miles. If axle is submerged underwater, replace fluid ASAP. | See Left 160,000 km |
Replace Front Differential Fluid | Not Provided; We Recommend changing fluid every 100,000 miles. If axle is submerged underwater, replace fluid ASAP. | See Left 160,000 km |
LB7 Duramax Oil, Fluid, And Filter Specs
If you want to keep your first generation Duramax running in excellent condition, you’re going to have to use the right fluid and oil. Not all fluids are created equal though. The best way to assure your LB7 Duramax gets the right fluids and oil is to stick with OEM recommended fluids. We recommend using OEM GM or ACDelco Fluids for everything. In the chart below, you’ll find the best engine oil, filters, and fluids to use for your LB7 Duramax. Click on one of the affiliate links in the chart to find that product on Amazon.
Fluid Type: | Part #: |
Engine Oil | 15W-40 ACDelco 15W-40 Shell Rotella T4 15W-40 Shell Rotella T5 15W-40 |
Engine Oil Filter | ACDelco PF2232 |
Fuel Filter | ACDelco TP3018 |
Coolant | Dex-Cool 12346290 50/50 mixture Pre-Diluted Dex-Cool 12378390 |
Water Pump Housing (Cover) | GM 97228188 |
Water Pump | GM 19168888 AC Delco 251-723 |
Thermostat Front Rear | See Below ACDelco 131-163 or GM 97241129 ACDelco 12T99D or GM 97241130 |
Mishimito Thermostats Warm Climate Kit: Cold Climate Kit: | Varies By Climate: Mishimoto MMTS-CHV-01DL Mishimoto MMTS-CHV-01DH |
Fan Clutch | GM/ACDelco 154964 |
Fan Blade | GM 1580690 |
Fan Pulley /w Bearing | ACDelco 1540039 |
Fan Shroud Upper Lower | See Below GM 15088324 GM 15196054 |
Radiator (OEM) Mishimoto Radiator | GM 21490 Mishimoto MMRAD-DMAX-01 |
Automatic Transmission Fluid | Dexron III Automatic Transmission Fluid AC Delco 10-9240 Replaced by Dexron VI Automatic Transmission Fluid – AC Delco 10-9243 |
Transmission pan gasket | 29549684 |
Internal Transmission Filter | Shallow Pan: 29537965 Deep Pan: 29542824 |
External Transmission Filter | ACDelco TF950 or Allison 29539579 |
Transmission Filter Kit | Shallow Pan Filter Kit Deep Pan |
Manual Transmission Fluid | TransSynd Synthetic Automatic Transmission Fluid 10-4029 OR GM 12378515 |
Automatic Transfer Case | Automatic Transfer Case Fluid Auto Trak 2 |
Manual Transfer Case | Dexron III Automatic Transmission Fluid ACDelco 10-9240 – Replaced by Dexron VI Automatic Transmission Fluid (AC Delco 10-9243) |
Front Differential Fluid | SAE 80W-90 |
Rear Differential Fluid | SAE 75W-90 |
LB7 Duramax Oil & Fluid Capacity
Fluid/Oil Type | Capacity – Quarts | Capacity – Liters |
Engine Oil /w Filter | 10 quarts | 9.5 Liters |
Coolant /w Auto Trans. /w Manual Trans. | See below 20.3 quarts 20.7 quarts | See below 19.2 Liters 19.6 Liters |
Automatic Transmission Refill: After Overhaul: | See Below 7.4 quarts 12.7 quarts | See Below 7 Liters 12 Liters |
ZF-6 Manual Transmission | 6.3 quarts | 6 Liters |
Transfer Case Manual Shift Auto Shift | See Below 2 quarts 2 quarts | See Below 1.9 Liters 1.9 Liters |
Front Differential 8.25″ Axle 9.25″ Axle | See Below 1.75 quarts 1.83 quarts | See Below 1.66 Liters 1.73 Liters |
Rear Differential 8.6″ Axle 9.6″ Axle 10.5″ Axle 11.5″ Axle | See Below 2.41 quarts 2.75 quarts 2.75 quarts 3.83 quarts | See Below 2.28 Liters 2.6 Liters 2.6 Liters 3.62 Liters |
Fuel Capacity Short Bed Long Bed | See Below 28 Gallons 34 Gallons | See Below 98 Liters 128 Liters |
Power Steering (Approximate) | .81-1.32 quarts | .77-1.25 Liters |
Want to Learn More about your truck?
Visit our other LB7 Duramax resources and informational articles. Click on one of the links listed below.
- LB7 Duramax Specs
- 9 Most Common LB7 Duramax Problems
- Best LB7 Duramax Performance Upgrades