For RAM 2500 and 3500 pickup trucks, the most potent engine choice is the Cummins 6.7 Turbo Diesel. Many fans of the engine often wonder about the 6.7 Cummins oil capacity. We’ll take a look at this in more detail later on in this post.
The engine, which is able to produce 400 HP and 1,000 pound-feet of torque, aids RAM in providing some of the best towing capabilities. The AISIN AS69RC six-speed automatic transmission is mated to it.
The RAM 3500 with a Cummins engine has a towing capacity of more than 31,000 pounds.
This renowned engine offers class-leading 15,000-mile oil change intervals and exceptional fuel efficiency. That kind of strength and dependability is unshakable.
- 6.7 Cummins
- Cummins Oil Capacity
- 6.7 Cummins Problems
- Cummins Years To Avoid
- Frequently Asked Questions
The most recent engine in the B series is the 6.7 Cummins diesel engine. It is a straight-six engine with 24 valves and a turbodiesel design that was introduced in 2007 for Dodge Ram pickups. This is not the type of engine you will not find in regular passenger cars like a John Cooper Works Clubman.
Even today, Ram 2500 and 3500+ vehicles use the 6.7 Cummins engine. It has, however, undergone several changes throughout the years.
The 6.7 Cummins engine has a powerful output of 400hp and gives 1000-pound feet of torque. Many people also link the Cummins brand to some of the greatest light truck diesel engines ever produced.
The 6.7 Cummins diesel isn’t flawless, but no engine is, and this is no exception.
In this post, we cover both general reliability and the most typical issues with the 6.7 Cummins engine.
6.7 Cummins Oil Capacity
With a filter replacement, a 6.7 Cummins engine requires 12 gallons of oil. Without changing the filter, the 6.7 Cummins oil capacity is 10.5 quarts.
This is for a Dodge Ram 2500/3500 truck with a 6.7 Cummins diesel engine that is 2010 model year or newer.
It’s critical to get the 6.7 Cummins oil capacity level precisely correct since either too much or too little oil in your engine might be hazardous.
Consult a skilled mechanic if you have any questions about how to check or add oil to your engine. They’ll be able to assist you in making sure your engine has the appropriate 6.7 Cummins oil type:
6.7 Cummins Oil Capacity, Oil Type #1 – Synthetic Oil
The recent turbo variant, one of the newest 6.7 Cummins engines, boasts an amazing 16:2:1 compression ratio when operating at full output
This indicates that the engine suffers from high-heat and high-pressure combustion.
Since synthetic oil can resist that additional strain on a molecular level, it is preferred for addressing certain circumstances. Yes, it costs more because all the components are synthetic.
6.7 Cummins Oil Capacity, Oil Type #2 – High-Mileage Engine Oil
The great majority of the time, high-mileage engine oil is a subtype of synthetic diesel oil designed for cars with more than 75,000 miles on the odometer.
Theoretically, these engines may run for up to 300,000 miles, but as the miles add up, it’s wise to change the oil.
High mileage oil is made with the same base oils as regular oil but also has conditioning agents and oxidation inhibitors as additions.
6.7 Cummins Oil Capacity, Oil Type #3 – High-Viscosity Motor Oil
Viscocity is important. The oil won’t successfully perform its function if it is too thin. The system cannot function if the oil is too thick.
Finding the ideal viscosity is crucial since it directly affects the 6.7 Cummins oil capacity to lubricate. Because high-viscosity oil is slick and can coat the parts more quickly, it lubricates more evenly.
You can understand coded viscosity remarks like 15W40 by referring to the SAE J300 viscosity chart, which includes particular measurements. The cold weather viscosity is indicated by the number to the left.
The heat tolerance is indicated by the number on the right. Consider your environment and the viscosity breakdowns before making your choice.
6.7 Cummins Oil Capacity, Oil Type #4 – Detergent Oil
No, we are not talking about getting a car wash. While every oil for 6.7 Cummins engines is derived from the same set of base oils, there are differences in the performance-enhancing additives.
Although some oils are completely devoid of detergents, these helpful substances are efficient at cleaning up flaws in the oil.
Due to the chemical makeup of magnesium sulfonates, the most popular detergent, it addresses deposits while still carrying out all of the key functions of motor oil and maintains structural integrity under pressure and heat.
6.7 Cummins Oil Capacity, Oil Type #5 – Conventional Oil
The standard method of powering your engine involves taking raw crude oil and refining it into a usable motor for your vehicle.
It originally appeared when Castrol began utilizing castor oil derived from minerals.
Even if it is still available, it is now far less prevalent.
The greater ratio of flaws is primarily to blame for this. However, both in terms of price and quality, it is less expensive. Even though the flaws might not cause problems straight away, using this kind of oil can cause problems.
The main lesson: Although synthetic oil outperforms natural/conventional oil for 6.7 Cummins engines, natural oil is fantastic in theory.
6.7 Cummins Problems
1. DPF Clogging
On the 6.7 Cummins, diesel particulate filter (DPF) blockage is a typical issue. Chrysler initially decided against employing diesel exhaust fluid (DEF).
To reduce NOx emissions, the 6.7 engine will run slightly richer when DEF is not present.
More particulates are produced as a result, and these can easily clog the DPF.
Early on, these clogging problems were so troublesome that Dodge spent a lot of its time and resources to lessen their frequency.
Diesel exhaust fluid and SCR emissions control systems are installed in Ram pickups in 2013.
As a result of the reduced particles, DPF blockage is less frequent on 6.7 Cummins models from later model years.
Many trucks are still impacted, especially as the mileage increases. Using a detergent option also reduces the frequency of oil changes.
The main lesson learned: Motor oils with detergent are significantly better than those without. If the damage isn’t too severe, it softens seals, enabling them to perform as intended.
On top of that, take note that older 6.7 Cummins engines are designed for high-mileage engine oil.
However, you can choose your preferred viscosity and treatment for these oils, making your purchase more personalized.
DPF Clogged Symptoms
The following signs suggest that the 6.7 diesel engine particle has a clogged filter:
- losing engine power
- takes a long time to crank
- reduced power mode (limp mode)
- OBD diagnostic codes
Power reduction in the 6.7 Cummins engine and a clogged DPF is one of the key signs you might observe.
There will be an increase in pressure if the exhaust gases cannot escape effectively. The 6.7’s engine and turbo performs badly as a result.
This is often true if the 6.7 Cummins DPF clogged forces you into low power mode. An engine trouble code may also be visible.
The DPF costs a lot to operate as emissions machinery. When compared to original filters, even a 6.7 DPF that has been rebuilt can cost more than $1,000. Owners of the 6.7 Cummins in a Dodge or Ram have a couple of options.
Diesel particulate filters with improved performance that are aftermarket are available, however, they frequently cost more than $1,000.
Pressure washing the OEM 6.7 DPF has proven effective for some. The filter may not even need to be cleaned, but even if it does, it will probably just be a temporary fix.
The 6.7 Cummins DPF is ultimately deleted in certain cases using an aftermarket exhaust, as a result of this.
The most cost-efficient and long-term successful option is unquestionably this one. But because of some legal issues, DPF deletions do have some drawbacks.
2. Head Gasket Issues
Compared to some other engines, the 6.7 Cummins does not have many head gasket issues. The 6.7, on the other hand, encounters this issue far more frequently than the 5.9 Cummins engines from the past.
It might be caused by the 6.7’s incredible amount of power and torque. The gasket failures could be caused by high amounts of pressure in the cylinder.
Head gasket problems may be exaggerated a little bit. So it’s probably not as frequent as some people might think.
However, given that replacing a head gasket can be somewhat expensive, it is still worthwhile to mention. Whenever the head gasket breaks, some people decide on upgrading fire rings as well as the head studs in an attempt to prevent the rising of the head.
6.7 Cummins Bad Head Gasket Symptoms
The following are signs of a faulty 6.7 Cummins head gasket:
- a sweet-smelling, white-ish smoke
- coolant and oil combined
- oil and coolant combined
It’s conceivable that a ruptured head gasket is going to allow the coolant to find its way inside the cylinders.
White exhaust smoke and a sweet-smelling coolant burn will follow this. Additionally, blown head gaskets on 6.7 Cummins engines can cause coolant and oil to mix.
Fast overheating of the coolant or the coolant pouring from the tank can also be a result of higher cooling system pressure.
6.7 Cummins Head Gasket Replacement
Depending on the type and year of the particular Ram or Dodge truck, replacement costs can change. Fortunately, the straight-six layout means that there is just a single head gasket. 6.7 head gaskets typically cost between $100 and $200.
The prices may start to mount, and the entire repair might cost more than $1,000. That also assumes that you won’t be replacing any components.
These kits are sought after by some owners of 6.7 Cummins to prevent any potential future problems. The kits are pricey, especially when work is included. But it’s good to at least use the head studs of the ISB 6.7 Cummins.
3. Fuel Dilution Problems
Okay, as we progress through the following portions, we’ll pick up the pace a little. The 6.7 engine naturally experiences fuel dilution in oil. Because of how the engine controls regeneration, it is innate.
Particulates are burned to ensure cleaner emissions during this procedure, where they are trapped inside the DPF. The seventh injector, which would inject fuel into the exhaust, is not a part of the 6.7 Cummins.
Instead, the fuel injectors will spray some fuel into the exhaust stream when the cylinders are in the exhaust strokes.
This enables tiny fuel particles to adhere to the wall of the cylinder, where they can combine with the oil. In practically all diesel engines, some fuel dilution happens. But some 6.7 Cummins appear to have excessive dilution.
The allowable limit, according to Ram and Dodge, is around 5% dilution.
Any higher can cause problems as excess fuel can prevent the oil from adequately lubricating and protecting the engine. The ISB 6.7 won’t sustain any immediate or severe damage. However, it may cause engine internals to prematurely wear out.
6.7 Cummins Fuel Dilution Symptoms
On the 6.7 Cummins, there are typically no noticeable initial indications of fuel dilution. As a result, performing regular oil analysis is a smart idea. You can use this to calculate the rate of fuel dilution in your diesel engine. Based on that information, you can create an oil change timetable.
Avoiding Cummins 6.7 Fuel Dilution
On the 6.7 Cummins, a few measures will help to prevent excessive fuel dilution, such as:
- Allow the engine to heat up.
- Avoid standing still for too long.
Before driving with significant engine loads, for example as while hauling large loads, give the engine time to warm up.
On a warmer engine, the fuel has a lower tendency to adhere to the walls of the cylinder. Additionally, avoid leaving the engine running for prolonged periods. This connects to the first point in a limited way.
The cylinder temperatures fall when the 6.7 Cummins is idled for an extended period. As a result, more fuel will attach to the cylinder walls.
4. 6.7 Cummins EGR Cooler Issues
EGR cooler problems plague a lot of contemporary diesel trucks. This is not an exception for the 6.7 Cummins. True, many of the components related to emissions in current diesels tend to cause problems.
Diesel owners who have owned their trucks for a long time are therefore probably aware of such issues. This will be pretty brief.
On the 6.7 Cummins, the cooler and EGR Valve can sometimes malfunction, especially at greater mileage. When issues do arise, it’s standard practice for the owners to merely uninstall the EGR system. EGR deletion can, of course, raise legal issues because of emissions regulations.
Sometimes simply cleaning the EGR valve will help to alleviate the problems. Though, it’s always a good idea to delete or replace the parts – especially when your Ram or Dodge has higher mileage.
5. 6.7 Cummins Turbocharger Failure
On previous model 6.7 Cummins engines, turbo issues or breakdowns are more prevalent. Turbochargers inherently endure a lot of abuse, therefore it could occur in any year.
Although the topic of this section is “turbo failure,” there are a few problems that might prevent it from happening entirely. Several potential problems with the 6.7 Cummins turbo include:
- Oil seals that leak
- Faulty bearings (too much shaft play)
- VGT parts that stick
- Damage to the turbine or compressor wheels
Wearing bearings and leaking oil seals are two of the most typical problems with older turbos. With 6.7 Cummins turbos, the engine can reach over 100,000 RPMs.
The 6.7 turbo bearings could degrade with time and result in too much shaft motion. Leaving the turbine or compressor wheel alone could result in contact.
Before overworking the 6.7 Cummins, it’s necessary to allow the oil to achieve operating temperatures because turbos operate on extremely hot exhaust gases.
A recipe for early turbo seal troubles is cold oil splashing on hot turbo seals. Before turning off the engine, you should also let the truck idle for a few minutes. This will facilitate turbo cooling.
Turbo issues can occur at any time, but they start to happen more frequently around 120,000 miles.
Possible turbo rebuild options exist. However, it could be wise to replace the entire turbo if your 6.7 Cummins has a lot of mileage on the old turbo.
6.7 Cummins Reliability
Many wonder if the 6.7 Cummins engine in the Ram or Dodge is reliable. No, and yes!
Looking at the 6.7 engine, it doesn’t exactly enjoy the same level of popularity as some more established models, such as 5.9 Cummins as well as 7.3 Power Stroke.
Many contemporary diesel engines, however, are in a similar situation to the Cummins 6.7. Many emissions-related technologies have the potential to seriously damage these diesels.
Some of the emissions components that can give the 6.7 Cummins engine headaches are DPF and EGR issues.
Nevertheless, the 6.7 Cummins is a generally dependable engine. This is especially true if you decide to remove certain emissions equipment, such as the DPF and EGR systems. But watch out for any emissions or repercussions on the law.
Otherwise, keep your 6.7 Cummins well-maintained and it should provide you with a good, dependable experience. To confirm fuel dilution, it is a good idea to undertake an occasional oil analysis.
Based on the outcomes, create a schedule for oil changes. As 6.7 Cummins faults happen, keep up with other routine maintenance and stay on top of repairs.
Again, compared to some of the older diesel engines, the 6.7 Cummins may not enjoy the same legendary status. The ISB 6.7 should continue to function well beyond 250,000 miles with proper maintenance. That’s a respectable amount of time, in our opinion.
6.7 Cummins Turbo Replacement Cost
The price of a brand-new OEM turbocharger starts at around $1,000 and frequently exceeds that amount.
The cost of a remanufactured turbo is between $1,000 and $1,500. Not cheap. For about the same price as OEM, if not less, you can buy some excellent 6.7 Cummins turbo improvements.
Our recommendation is to opt for turbo improvements. You will be able to get a little bit more performance out of your Dodge or Ram pickup.
Even if OEM performance is often a preference, turbo upgrades will still be an excellent choice. It will be simpler to operate and, in principle, a bigger and more efficient turbo should last much longer compared to the OEM turbo.
6.7 Cummins Years To Avoid
Since 1989, the Dodge Cummins engine has been the power behind the Dodge Ram. After working so hard for three decades, there will undoubtedly be some Dodge Cummins years to avoid. Avoiding the 1991, 1992, 1993, 1999, 2001, 2003, 2006, 2007, 2008, and 2011 models is a smart move.
These years have led to several problems. A few of the frequent ones take the shape of transmission problems, charging system issues, and electrical problems. Any driver would find dealing with this to be inconvenient and expensive.
Best Dodge Cummins Engines To Buy Used
You should avoid the Dodge Cummins models from several years, but there is also a number that is secure to purchase second-hand. Concerning this engine kind, let’s discuss a few of your top options.
These are some of the Dodge Cummins investments that many owners cite as being among the safest:
Dodge Cummins models from 2004 to 2005, 2009 to 2010, and so on
2012 Dodge Cummins 2013, 2014 Dodge Cummins 2015 Dodge Cummins 2016, 2017 Dodge Cummins 2018, 2019 Dodge Cummins, and 2020 Dodge Cummins.
When compared to other years on the market, these engines stand out as the superior choice.
Even with these suggested engines, you will still notice issues just as with any other vehicle. Among the most frequent are stability control and engine failure issues. Nevertheless, they happen less frequently in these years than in the ones to avoid with the Dodge Cummins.
You can buy with confidence knowing you’re getting the best if you buy one of these years. These are the most dependable years.
Frequently Asked Questions
How Much Oil Does A 6.7 Cummins Take
Most 6.7 Cummins-powered vehicles need 12 quarts of oil for a full oil change. It depends on the state of your car and the type of oil you’re using for top-ups. Particularly the earlier models of Cummins are notorious for using a lot.
When Did The 6.7 Cummins Come Out
Early in 2006, the Dodge Ram Chassis-Cab debuted with a 6.7-liter Cummins turbo-diesel engine intended for commercial use.
What Cummins Engine Is The Best
This renowned diesel engine is currently available as the Cummins 6.7L Turbo Diesel. It is the greatest Cummins engine currently available because of its wealth of features.