Comprehensive LML Duramax Service Schedule
Maintenance Guide for 2011-2016 Chevy HD & GMC HD trucks featuring the 6.6L LML Duramax Diesel Engine
It’s no secret that Diesel engines, if properly taken care of, can last decades. Every day you probably drive by diesel trucks from the 1990’s or even the 80’s. How can you make sure your diesel truck lasts just as long? The biggest factor is preventative maintenance. If you take care of your truck, it will take care of you. What maintenance and service tasks can you complete to preserve your LML? Everything you need is in this comprehensive LML Duramax service schedule. Everything in our maintenance guide listed below is based off of GM’s recommended LML Duramax maintenance intervals.
LML Duramax Service Schedule: Normal Conditions
The frequency at which you will need to complete maintenance on your LML Duramax vary greatly. If you are constantly driving in heavy traffic, idling excessively, or towing heavy loads you will need to follow GM’s Severe maintenance schedule. Otherwise, the normal LML Duramax service schedule is just fine.
| Maintenance/Service | Miles | Kilometers |
| Change Oil | 7,500 miles | 12,000 km |
| Rotate tires | 7,500 miles | 12,000 km |
| Change Oil Filter | 7,500 miles | 12,000 km |
| Change Fuel Filter | Every 22,500 miles or when CHANGE FUEL FILTER message displays | 36,000 km |
| Replace Air Filter | 45,000 miles | 72,000 km |
| Change Cabin Air Filter | 22,500 miles or every 2 years | 36,000 km |
| Flush Cooling System | 150,000 miles or every 5 years | 240,000 km |
| Replace Transmission Fluid | 45,000 miles | 72,000 km |
| Change External transmission filter | 45,000 miles | 72,000 km |
| Change internal transmission filter | 97,500 miles | 156,000 km |
| Replace Transfer Case Fluid | 97,500 miles | 156,000 km |
| Replace Rear Differential Fluid | GM doesn’t mention any recommended service intervals; we recommend every 100,000 miles or sooner | 160,000 km |
| Replace Front Differential Fluid | GM doesn’t mention any recommended service intervals; we recommend every 100,000 miles or sooner | 160,000 km |
LML Duramax Maintenance Schedule: Severe Conditions
| Maintenance/Service | Miles | Kilometers |
| Change Oil | 7,500 miles | 12,000 km |
| Rotate Tires | 7,500 miles | 12,000 km |
| Change Oil Filter | 7,500 miles | 12,000 km |
| Change Fuel Filter | Every 22,500 miles or when CHANGE FUEL FILTER message displays | 36,000 km |
| Replace Air Filter | 45,000 miles | 72,000 km |
| Flush Cooling System | 150,000 miles or every 5 years | 240,000 km |
| Replace Transmission Fluid | 45,000 miles | 72,000 km |
| Change External transmission filter | 45,000 miles | 72,000 km |
| Change internal transmission filter | 45,000 miles | 72,000 km |
| Replace Transfer Case Fluid | 22,500 miles | 36,000 km |
| Replace Rear Differential Fluid | GM doesn’t mention any recommended service intervals; we recommend every 100,000 miles or sooner | 160,000 km |
| Replace Front Differential Fluid | GM doesn’t mention any recommended service intervals; we recommend every 100,000 miles or sooner | 160,000 km |
LML Duramax Maintenance Parts List
When swapping filters or changing the oil on your 6.6L LML Duramax you need to use parts that meet or exceed OEM specifications. I recommend using OEM parts from GM or ACDelco. By using OEM parts, you can guarantee you’re consistently getting quality parts. Links directly to these products on Amazon are listed below.
| Part Type | Part # | Amazon Link |
| Engine Oil | 15W-40 | ACDelco 15W40 Shell Rotella T4 15W40 |
| Engine Oil Filter | PF2232 | PF2232 |
| Fuel Filter | ACDelco TP3018 23304096 | ACDelco TP3018 |
| Cabin Air Filter | CF 188 | ACDelco CF 188 |
| Engine Air Filter | ACDelco A3141C | ACDelco A3141C |
| Coolant | Dex-Cool 12346290 50/50 Mix | Dex-Cool 12346290 |
| Transmission Fluid | Dexron VI Full Synthetic | Dexron VI |
| External Transmission Filter | ACDelco TF950 Allison 29539579 | ACDelco TF950 Allison 29539579 |
| Internal Transmission Filter | GM 29542833 | GM 29542833 |
| Transfer Case Fluid | Dexron VI Full Synthetic | Dexron VI |
| Front Differential Fluid | SAE 75W-90 Synthetic Axle Lubricant | 75W90 |
| Rear Differential Fluid | SAE 75W-90 Synthetic Axle Lubricant | 75W90 |
| Diesel Exhaust Fluid | N/A | Peak BlueDEF |
Learn More About The LML Duramax
Want to learn more than about your LML? Check out our other posts about the LML Duramax.
ABOUT Kamil
Founder of Diesel Resource and a complete diesel head. Has a little bit of problem buying too many trucks. Learn more about him by checking out his truck.