If you own a 2017–2024 Ford 6.7L Power Stroke, Ram 6.7L Cummins, or GM 6.6L L5P Duramax, the factory maintenance schedule is the best place to start. All three manufacturers moved to oil-life monitors years ago, so "change it every 5,000 miles" isn't the rule anymore. The monitors only work if you understand them, though, and the fixed-interval items like fuel filters, air filters, and coolant still trip people up. This guide puts the published factory intervals side by side, explains where severe-duty use changes them, and lists the parts you'll need for each service.
Important: Always confirm against the owner's manual or diesel supplement for your exact model year. Manufacturers revise schedules, and the intervals below come from the specific documents linked in each section.
Quick comparison: factory intervals at a glance
| Service | Ford 6.7L Power Stroke | Ram 6.7L Cummins | GM 6.6L L5P Duramax |
|---|---|---|---|
| Engine oil & filter | When the Intelligent Oil-Life Monitor says so. Typically 7,500–10,000 mi in normal use, never more than 1 year/10,000 mi | When the oil change indicator says so. Never more than 15,000 mi, 12 months, or 500 hours | When the Engine Oil Life System shows CHANGE ENGINE OIL SOON. Do not exceed 10,000 mi/1 year (commonly cited) |
| Fuel filters | Engine- and frame-mounted every 30,000 mi (normal), 15,000 mi under Ford's special operating conditions | Engine- and chassis-mounted every 15,000 mi / 12 months | When the Fuel Filter Life monitor shows CHANGE FUEL FILTER (often cited as about 22,500 mi / 2 years) |
| Engine air filter | Every 30,000 mi; check the restriction gauge at every oil change | Inspect every 15,000 mi, replace as needed | When the Engine Air Filter Life display calls for it |
| Water separator | Drain at oil changes or when the water-in-fuel light comes on | Drain when indicated | Drain at fuel filter service or when indicated |
Ford 6.7L Power Stroke (2017–2024)
Oil changes: trust the monitor, but know its ranges
Ford's normal scheduled maintenance for Super Duty diesels says the Intelligent Oil-Life Monitor decides when the engine oil and filter get changed. Ford publishes the ranges you should expect to see: about 7,500–10,000 miles for normal commuting with light or no towing, 5,000–7,500 miles for moderate-to-heavy towing, mountain driving, or extended idling, and 3,000–5,000 miles for maximum-load towing or extreme temperatures. Ford also says not to go more than one year or 10,000 miles between services. (Source: Ford Normal Scheduled Maintenance.)
The manual lists more than one viscosity grade depending on climate, so check the oil chart for your year before you buy. We carry complete kits in both common grades: the 6.7L Power Stroke 5W-40 oil change bundle with OE filter and the 6.7L Power Stroke 10W-30 oil change bundle with OE filter. Aftermarket-filter versions are also available.
Fuel filters: two of them, and they matter
The 6.7L Power Stroke has an engine-mounted filter and a frame-mounted filter/water separator. Ford's normal schedule replaces both every 30,000 miles. Ford's own fuel filter service sheet lists 15,000 miles / 600 engine hours under special operating conditions: extensive towing, long idle time, extended low-speed driving, biodiesel use, or dusty conditions. Ford also recommends draining the water separator at every oil change, or immediately if the WATER IN FUEL light comes on. (Source: Ford diesel fuel filter service sheet.)
The Power Stroke 6.7L oil and fuel filter bundle lets you do both jobs at once.
Other Ford items
- Cabin air filter every 20,000 mi; engine air filter every 30,000 mi.
- Engine coolant: first change at 6 years/100,000 mi, then every 3 years/50,000 mi.
- Automatic transmission fluid and filter, axles, and transfer case: 150,000 mi on the normal schedule. Towing-heavy trucks should follow the severe schedule in the manual.
Ram 6.7L Cummins (2017–2024)
Oil changes: 15,000 miles is a ceiling, not a target
Ram's diesel maintenance plan says to change engine oil every 15,000 miles, 12 months, or 500 hours, or sooner if the oil change indicator calls for it, whichever comes first. The indicator is duty-cycle based, so a truck that tows heavy or idles a lot will get the message earlier. Ram also recommends checking the oil level every 3,000 miles. (Source: 2022 Ram 2500/3500 Maintenance Plan — Diesel Engine.)
For 2019 and newer trucks, the 2019–2026 Ram 6.7L oil and fuel filter bundle (OE filters) covers the oil filter and both fuel filters. We also stock a Ram 6.7L 10W-30 oil change bundle and a 15W-40 oil change bundle. Match the grade to your manual's temperature chart.
Fuel filters every 15,000 miles
The same Ram schedule has you replace both the engine-mounted and chassis-mounted fuel filters every 15,000 miles. That's every other oil change if you run the full 15,000-mile interval, or every oil change if your indicator brings you in at 7,500. The common-rail injection system on the Cummins depends on clean, dry fuel, so this is not an interval to stretch.
Other Ram items
- Cabin air filter every 12,000 mi; inspect the engine air filter every 15,000 mi.
- Crankcase ventilation (CCV) filter at 75,000 and 150,000 mi on the plan. The cluster shows "Perform Service" when it's due.
- Transmission fluid intervals depend on whether you have the 68RFE or the Aisin AS69RC, and on whether you tow frequently. Check your manual.
GM 6.6L L5P Duramax (2017–2024)
Oil changes: the Engine Oil Life System
GM's Duramax diesel supplement says the Engine Oil Life System calculates oil life from how you use the truck and displays CHANGE ENGINE OIL SOON when the oil and filter are due. Reset it to 100% only after an oil change. GM also specifies a dexos D-approved diesel oil. Use the viscosity your supplement lists for your year and climate. (Source: GM 6.6L Duramax Diesel Supplement.) Many service references also say not to go past 10,000 miles or one year between changes, even if the monitor reads higher.
For 2017–2019 L5P trucks, the L5P OE oil and fuel filter bundle combines both services. Browse the full 6.6L Duramax parts collection for later years.
Fuel filter: the monitor tells you
The L5P has a Fuel Filter Life Remaining display. When it's low you'll see CHANGE FUEL FILTER, and you have to reset the monitor yourself after the filter change because it won't reset on its own. Independent references commonly cite about 22,500 miles or 2 years. The filter sits inside the driver-side frame rail. We carry a 2017–2026 L5P replacement fuel filter.
Air filter
The L5P also has an Engine Air Filter Life display that gives you a REPLACE AT NEXT OIL CHANGE warning before REPLACE SOON. See the 2017–2019 L5P drop-in air filter or the filters collection.
What counts as "severe duty"?
All three manufacturers shorten their intervals for the same kinds of use, and plenty of diesel owners fall into at least one of them:
- Frequent trailer towing or hauling near maximum payload
- Extended idling, such as job sites, plowing, or work trucks
- Dusty, off-road, or mountainous driving
- Extreme heat or cold
- Biodiesel blends above what your engine is rated for
If that describes your truck, use the severe schedule and expect the oil-life monitor to call for service earlier. That's normal and not a fault.
Build a simple maintenance log
For each service, write down the date, mileage, engine hours, oil-life percentage at the time of the change, and the part numbers you used. It helps with warranty claims and resale, and it lets you spot problems early, like water showing up at every fuel filter change.
Ready to stock up? Shop oils & fluids, filters, or go straight to your engine: 6.7L Power Stroke, 6.7L Cummins, 6.6L Duramax.
FAQ
Can I really go 15,000 miles between oil changes on my Cummins?
Only if the oil change indicator lets you get there first. Ram sets 15,000 miles, 12 months, or 500 hours as the maximum and tells you to change sooner if the indicator says so. Trucks that tow often usually get the prompt well before 15,000.
Does Ford really say 30,000 miles for 6.7L fuel filters?
That's on Ford's normal schedule. Ford's fuel filter service sheet cuts it to 15,000 miles / 600 hours for towing, idling, low-speed, biodiesel, or dusty use, which covers a lot of real-world diesel trucks.
Do I need to reset the monitors myself?
Yes, if you do the service yourself. Ford, Ram, and GM all describe reset procedures in the owner's manual. On the L5P, the fuel filter monitor has to be reset separately from the oil life monitor.
Will doing my own maintenance void my warranty?
In the U.S., you can generally do your own maintenance as long as you use parts that meet the manufacturer's specifications and keep records. Save your receipts and your log.
Which oil viscosity should I use?
Use the grade and spec in your owner's manual for your year and climate. We stock the common diesel grades in complete change kits so you can match it.