Ram 2500 Oil Capacity & Oil Type
TL;DR
Verified figure: 6.7L Cummins diesel (2007.5-present) = 12 US qt (11.4 L) with filter. For the 5.7L and 6.4L HEMI gas V8s, confirm the exact quart figure on your own filler cap or owner's manual rather than relying on a single published number.
Why the engine code matters more than the model name
Ram 2500 has been sold with at least three very different engines - the 5.7L HEMI V8 (gas, earlier trucks), the 6.4L HEMI V8 (gas, current heavy-duty gas option) and the 6.7L Cummins inline-six turbo-diesel (offered since mid-2007). Oil capacity is a property of the engine, not the model name, so the right number depends entirely on which engine is under the hood.
Verified: 6.7L Cummins turbo-diesel
Manufacturer engine data for the 6.7L Cummins (badged ISB from 2007.5-2017 and B6.7 from 2017 onward, both used in the Ram 2500) lists the oil system capacity with a new filter as 3 US gallons - equal to 12 US quarts or 11.4 liters. This is the one figure on this page we could independently confirm against a manufacturer-sourced spec.
5.7L and 6.4L HEMI gas V8s - confirm before you buy oil
The gas-engine HEMI V8s used in the Ram 2500 hold noticeably less oil than the diesel, and the exact quart figure has been reported inconsistently across aftermarket sources for different model years and running changes. Rather than repeat an unverified number, we recommend reading it directly off your engine: the oil fill quantity is stamped or printed near the oil filler cap on most HEMI engines, and it is always listed in the Maintenance or Capacities section of your owner's manual.
Viscosity - always confirm on your own vehicle
Recommended oil viscosity (for example a 5W-20, 5W-40 or 0W-40 grade) has changed across Ram 2500 model years and between the gas and diesel engines, and low-viscosity synthetic requirements have tightened over time for emissions reasons. Do not guess this from a forum post - the correct grade for your specific truck is printed on the oil filler cap, listed in the owner's manual Capacities and Refill chart, and also shown on the underhood emissions/VECI label.
Where to find the authoritative number for your truck
- Oil filler cap - many engines have the quart capacity and viscosity printed directly on or near the cap
- Owner's manual - the Maintenance or Technical Specifications chapter has a full fluid capacity table by engine
- Driver's door jamb placard - primarily tire and loading info, but often cross-references the manual section
- Manufacturer towing guide / RV and trailer towing guide - published yearly by Ram and includes engine-specific service data
| Engine code / years | Capacity with filter (L / US qt) | Viscosity |
|---|---|---|
| 6.7L Cummins I6 turbo-diesel, ISB (2007.5-2017) | 11.4 L / 12 US qt (verified) | Check filler cap and owner's manual - diesel-rated oil, grade varies by year and climate |
| 6.7L Cummins I6 turbo-diesel, B6.7 (2017-present) | 11.4 L / 12 US qt (verified) | Check filler cap and owner's manual - diesel-rated oil, grade varies by year and climate |
| 6.4L HEMI V8 gas (2010-present) | Not independently verified here - see filler cap or owner's manual | See filler cap or owner's manual |
| 5.7L HEMI V8 gas (2003-2009 Ram 2500) | Not independently verified here - see filler cap or owner's manual | See filler cap or owner's manual |
Summary
| 6.7L Cummins (ISB, 2007.5-2017) capacity with filter | 11.4 L / 12 US qt (verified) |
|---|---|
| 6.7L Cummins (B6.7, 2017-present) capacity with filter | 11.4 L / 12 US qt (verified) |
| 6.4L HEMI V8 gas capacity with filter | Check filler cap / owner's manual - not verified here |
| 5.7L HEMI V8 gas capacity with filter | Check filler cap / owner's manual - not verified here |
| Diesel oil viscosity | Varies by year and climate - see filler cap / manual |
| Gas HEMI oil viscosity | Varies by year - see filler cap / manual |
| Best source for your exact truck | Oil filler cap plus owner's manual Capacities chart |
Full diagnostics
For the complete step-by-step diagnostic and repair guide, see Ram 2500: Common Problems, Fault Codes & Repairs.
Frequently asked questions
How much oil does a Ram 2500 with the 6.7L Cummins diesel take?
Manufacturer engine data for the 6.7L Cummins (ISB, 2007.5-2017, and B6.7, 2017-present) lists 3 US gallons with a new filter, which is 12 US quarts or 11.4 liters. This figure applies to the 6.7L diesel engine specifically, not to the gas HEMI engines also offered in the Ram 2500.
Does the oil capacity differ between the 5.7L and 6.4L HEMI gas engines?
Almost certainly yes, since they are different displacements and years, but we were not able to confirm one reliable, source-backed quart figure for either gas engine at the time this page was written. Check the oil filler cap on your engine or the Capacities table in your owner's manual for the exact number on your truck.
What oil viscosity should I use in my Ram 2500?
It depends on the engine and model year, and requirements have changed over time (for example some years call for 5W-40 or 0W-40 synthetic on the diesel and a different grade on the gas HEMI). The correct viscosity for your specific truck is printed on or near the oil filler cap and listed in the owner's manual Capacities and Refill chart - use that rather than a generic figure.
Where is the most reliable place to check my own truck's exact oil capacity?
Start with the oil filler cap, which on many Ram engines has the quart figure stamped nearby, then confirm with the Maintenance or Technical Specifications section of your owner's manual, which lists capacity by engine code. These two sources reflect your exact engine and model year, which a general web page cannot guarantee.