How much oil does a 6.7 l diesel take?

For most 6.7-liter diesel engines, you’ll be looking at roughly 15 quarts of oil when you replace the oil and filter, about 14 liters. The exact figure depends on the engine family and whether you’re changing the filter.

Common 6.7L diesel variants and their oil capacity

The following figures reflect typical capacities for two widely used 6.7L engines found in everyday trucks. They assume a full oil change with the filter replaced and a new filter installed.

• Ford 6.7L Power Stroke V8 (used in Ford Super Duty from 2011 onward): Oil capacity with filter is 15 quarts (14.2 L). Model-year variations may adjust this by a small amount; consult the owner’s manual for the exact number.


• Ram 6.7L Cummins ISB (in Ram 2500/3500 from 2007 to present): Oil capacity with filter is typically about 12–15 quarts (11.4–14.2 L), with many sources citing around 13 quarts (12.3 L) as common; year and filter type can shift the figure.

These figures provide a practical target for planning an oil change, but the precise capacity should come from your vehicle’s manual or a service bulletin. Always verify before filling to avoid overfill or underfill.

What affects the final capacity and how to fill correctly

There are several factors that influence the exact amount of oil a 6.7L diesel will take. Engine variant, oil filter size, and whether the engine is being filled from a drained state all matter. When performing an oil change, follow the manufacturer’s recommended capacity and procedure to ensure proper lubrication and engine protection.

Follow these steps to perform an oil change properly on a 6.7L diesel engine:

1. Warm up the engine briefly, then switch off and let the oil settle.


2. Place a drain pan beneath the drain plug and remove it to drain the old oil completely.


3. Remove and replace the oil filter with a new one that matches your engine’s specification.


4. Reinstall the drain plug and slowly add oil up to the lower end of the recommended capacity range, as stated in your manual.


5. Start the engine, run for a few minutes, then shut off and check for leaks.


6. Recheck the oil level with the dipstick and top up gradually until it reaches the proper mark.

Correctly filling and checking the oil helps prevent overfill or underfill, which can affect performance and engine longevity.

Summary

In practical terms, a 6.7L diesel typically takes about 12–15 quarts of oil when including a new filter, with Ford’s Power Stroke generally at the higher end (around 15 quarts) and Ram’s Cummins varying around 12–13 quarts for many configurations. Always confirm the exact capacity from your owner’s manual or dealership documentation, and use the dipstick to verify the final level after an oil change.

What kind of oil does a 2019 6.7 Powerstroke take?

For a 2019 6.7 Powerstroke, the recommended oil is SAE 10W-30 meeting spec WSS-M2C171-F1 for normal driving conditions. However, 5W-40 full synthetic is recommended for severe duty or if using biodiesel blends (B20 max). The oil capacity is 13 quarts, including the filter. 
Oil recommendations

• Normal driving: SAE 10W-30 meeting Ford specification WSS-M2C171-F1. 
• Severe duty or biodiesel use: SAE 5W-40 meeting Ford specification WSS-M2C171-F1. 
• Extreme cold: In temperatures below -22°F (-30°C), you can use 0W-40 oil. 

Why choose a specific type?

• Severe duty: Activities like frequent towing, heavy loads, or extensive idling are considered severe duty. For these conditions, the thicker 5W-40 provides better protection. 
• Biodiesel: If you are using up to a B20 blend of biodiesel, 5W-40 or 15W-40 is recommended. 
• Full synthetic: Full synthetic oils like 5W-40 offer improved performance in both extreme cold and high-heat conditions compared to conventional oils. 

Other considerations

• Capacity: The 6.7 Powerstroke requires 13 quarts of oil, including the filter. 
• Specifications: Always ensure the oil meets the specific Ford specification, WSS-M2C171-F1, to avoid potential engine damage or voiding the warranty. 
• Brand: Many reputable brands, such as Amsoil, Rotella, and Valvoline, offer oils that meet these requirements. 

Should I run full synthetic oil in my 6.7 powerstroke?

For superior cold-weather performance, 0W-40 full synthetic diesel motor oil is the best choice. This multigrade oil benefits the 6.7 Powerstroke in both freezing and hot temperatures.

Can I put 15w40 in my 6.7 Cummins?

You can put 15W-40 in a 6.7 Cummins, but only for pre-2019 models, as it is not recommended for newer models. Newer 2019 and later 6.7 Cummins engines require a thinner oil, such as 10W-30 or 5W-40, because the thicker 15W-40 can cause deposits on hydraulic lifters and lead to slow pressurization. Always use a low-ash diesel oil that meets API CJ/CK-4 and Cummins CES 20081 standards. 
For 6.7 Cummins engines

• 2007–2018 models: Use 15W-40 or 5W-40, depending on your climate. 
• 2019+ models: Use 10W-30 or 5W-40. 15W-40 is not recommended and can cause issues. 

Before you use 15W-40

• Check your owner's manual: This is the most definitive source for your specific truck. 
• Consider the climate: If you operate in consistently cold temperatures, a thinner oil like 5W-40 is a better choice even for older models. 
• Use the correct specifications: Regardless of the viscosity, ensure the oil is a low-ash diesel oil that meets API CJ/CK-4 and Cummins CES 20081 standards. 

What is the best oil for a Ford 6.7 diesel engine?

The best oil for a Ford 6.7L diesel engine is 5W-40 full synthetic diesel motor oil for severe duty, towing, or colder climates, or 10W-30 for normal conditions in warmer climates. Full synthetic 5W-40 offers superior cold-start performance and protection. Many owners also choose brands like Rotella T6 or Amsoil for their high-quality synthetic oils. 
Oil options

• 5W-40 full synthetic: This is the best choice for most users, especially those who do heavy towing, experience stop-and-go traffic, or live in colder climates. It provides excellent protection during cold starts and maintains viscosity under high temperatures. 
• 10W-30: This is the recommended grade for "normal" driving conditions, but it is not recommended for severe duty or biodiesel use. It is a good option for warmer climates. 
• 15W-40: This is acceptable for severe use in warmer climates or when using biodiesel, but it can cause more engine wear in colder temperatures compared to 5W-40. 

Key considerations

• Severe vs. normal duty: Many owners consider their driving habits to fall under "severe duty" due to towing, idling, or stop-and-go traffic, making 5W-40 the better choice. 
• Climate: In very cold climates, 0W-40 or 5W-40 full synthetic oils are superior for cold starts. In warmer climates, 10W-30 or 15W-40 are suitable options. 
• Biodiesel: If you run biodiesel, you should use a 5W-40 or 15W-40 oil. 

How to choose

• Check your owner's manual: Always refer to the oil viscosity recommendation on your vehicle's oil fill cap or in your owner's manual. 
• Consider your driving conditions: If you frequently tow, drive in stop-and-go traffic, or idle for extended periods, choose 5W-40 full synthetic for superior protection. 
• If in doubt, go with 5W-40: For most 6.7L owners, 5W-40 full synthetic provides the best all-around protection and performance.