How Much Oil Does a 6.7 Cummins Take?

If you're standing in the parts store, sitting in your driveway with a drain pan under the truck, or just picked up a used Ram and want to plan ahead, you need a clear number. Here it is, plus the year-by-year details, the right oil to put in, and how to do the change without overfilling.

6.7 Cummins Oil Capacity at a Glance

A 6.7 Cummins takes 12 quarts (3 gallons, or 11.4 liters) of oil with a filter change for most model years. Without changing the filter, you'll need closer to 11 quarts.

That's the answer for nearly every Ram 2500, 3500, 4500, and 5500 from 2007.5 onward, and it'll get you through 95% of oil changes. The exceptions, the right oil weight, the filter to grab, and how to actually do the change are below.

One tip before you start: pour 11 quarts first, run the engine for a minute, let it sit, then check the dipstick and top off from there. That's how seasoned owners do it, and it's the easiest way to keep from overfilling.

Oil Capacity by Model Year

The 6.7 Cummins has stayed pretty consistent since it replaced the 5.9, but there are a few year-specific things worth knowing.

2007.5 to 2018 Models

These trucks all take 12 quarts with a filter change, or about 11 quarts without. Whether you've got the original 350-horsepower 2007.5 truck or one of the later high-output versions, the oil capacity is the same. If you're working on a Ram 2500 or 3500 pickup from these years, the number is 12. End of story.

2019 to 2024 Models

This is where it gets a little muddy online. Most sources, including the owner's manual for the standard pickup applications, list 12 quarts with a filter change. A few sources list 10 quarts for 2019 and newer trucks.

The difference usually comes down to engine variant. The standard-output 6.7 in a Ram 2500 still takes 12 quarts. Some newer high-output and cab-and-chassis variants ship with a different oil pan and call for less. Always check your owner's manual or the sticker under the hood before you buy.

The safe move: grab 12 quarts (3 gallons), pour 10 to start, and check the dipstick. If your truck reads full at 10, you've got 2 quarts left for top-offs down the road.

Cab and Chassis Trucks

3500, 4500, and 5500 cab-and-chassis trucks (the ones that get hauler beds, flatbeds, and service bodies) sometimes use different oil pan setups than pickups. Many are still 12 quarts, but some commercial configurations run different capacities.

If you're working on a fleet truck, a tow truck chassis, or anything that started life as a "build-your-own-bed" platform, check the manual or the underhood sticker. Don't assume the pickup number applies.

The Right Oil and Filter for Your Truck

Capacity is half the question. The other half is what to actually put in.

Best Oil Weight by Climate

The standard recommendation for the 6.7 Cummins is 15W-40 in temperatures above 0°F (about -18°C). It's the workhorse oil and what most shops use.

If you live somewhere it gets really cold (think Minnesota, Maine, or anywhere that hits sub-zero temps regularly), step down to 5W-40 full synthetic. The lighter cold-start viscosity flows better when the engine is stone cold and saves wear on those rough mornings.

The oil needs to meet API CK-4 (or the older CJ-4) and ideally the Cummins CES 20081 spec. That's the standard that confirms it has the right detergent and zinc levels for a heavy-duty diesel. Solid choices you can grab anywhere: Shell Rotella T6, Mobil Delvac, Valvoline Premium Blue, and Amsoil Heavy Duty.

Synthetic costs more upfront but holds up longer between changes and protects better in extreme heat or cold. For a daily-driven truck, it's worth the extra few bucks per gallon.

Recommended Oil Filter

The OEM filter is the Fleetguard LF16035 for most 2007.5 to current 6.7 Cummins trucks. It's also sold under the Mopar/Cummins part number, but it's the same filter from the same factory.

Solid aftermarket options: WIX 57620, Donaldson P550425, and Baldwin B7577. All three meet or exceed OEM specs and usually cost a few bucks less.

What to skip: ultra-cheap no-name filters from sketchy Amazon or eBay sellers. The 6.7 moves a lot of oil through that filter at high pressure, and a bad filter is one of the few ways you can damage this engine cheaply.

How to Change Your Oil Without Overfilling

Here's the no-headaches procedure most owners follow.

Step 1: Warm the engine for a couple of minutes. Don't get it fully hot. Just enough to thin the oil so it drains cleanly. A two-minute idle is plenty.

Step 2: Drain the oil and let it sit for 15 to 20 minutes. The first 90% comes out in the first five minutes. The rest is slow drips. Pull the oil fill cap on top of the engine to help it drain faster.

Step 3: Replace the filter. On most 6.7 Cummins trucks, the filter is mounted on the oil cooler housing. Twist it off, lube the new gasket with a dab of fresh oil, and hand-tighten the new one. Don't crank it down with a wrench.

Step 4: Pour 11 quarts and start the engine. Let it idle for 30 to 60 seconds, watch for leaks at the filter and drain plug, then shut it down.

Step 5: Wait five minutes, then check the dipstick. The dipstick has about a one-quart range between the low and full marks. If you're below the full mark, top off with the remaining oil a half-quart at a time, checking after each pour. Stop when the stick reads in the upper third of the range. You don't need to peg it at the very top.

The whole job takes about 30 to 45 minutes once you've done it once.

How Often to Change Your Oil

Cummins recommends 15,000 miles or 12 months for 2013 and newer trucks under normal use, whichever comes first. Older 2007.5 to 2012 trucks were originally spec'd at 7,500 miles, though plenty of owners run them longer with a quality synthetic.

Cut those intervals in half for severe service. That includes regular heavy towing, lots of stop-and-go traffic, dusty environments, frequent cold starts, or trucks that idle for long stretches (work trucks, construction rigs, and the like).

Not sure where your truck falls? An oil analysis from a service like Blackstone Labs costs about $30 and tells you exactly when your oil needs to come out based on its actual condition. It's the smart move for anyone who wants to dial in their intervals.

FAQs

How much oil does a 6.7 Cummins take without a filter change?

About 11 quarts. The oil filter holds roughly half a quart to a full quart on its own, so skipping the filter swap means you put back a little less. That said, it's not really worth doing an oil change without changing the filter. A new one is $15 to $25, and it's the cheapest insurance you can buy for this engine.

Can I use regular passenger car motor oil in my 6.7 Cummins?

No. Diesel oil has more zinc, more detergent, and a different additive package than gas-engine oil. Running passenger car oil in a 6.7 Cummins will lead to soot buildup, premature wear, and potential damage to the high-pressure fuel system. Stick with oil that says CK-4 or CJ-4 on the bottle and ideally meets the Cummins CES 20081 spec.

What happens if I accidentally overfill my engine?

A small overfill (half a quart) is no big deal. A serious overfill (a quart or more above the full mark) can cause foaming, blow oil past the seals, saturate the CCV filter, and stress the crankshaft. If you've overfilled by more than half a quart, drain some out through the drain plug or pull it with a dipstick-tube extraction pump.

How long should I let the oil drain before refilling?

15 to 20 minutes is plenty for most jobs. The bulk of the oil comes out in the first five minutes. The rest is slow drips that don't add up to much. Some guys leave it overnight to be thorough, but it's not strictly necessary.

More reading:What Is the Best Delete Kit for 6.7 Cummins?