10 Best Oil for 6.7 Cummins [Reviews & Buying Guide]

It shouldn’t be surprising to know that diesel engines require particular and rigorous care to keep them performing optimally. The 6.7 Cummins is a range of diesel engines developed by RAM for its 2500 and …

It shouldn’t be surprising to know that diesel engines require particular and rigorous care to keep them performing optimally. The 6.7 Cummins is a range of diesel engines developed by RAM for its 2500 and 3500 trucks, replacing the older 5.9L ISB diesel engine.

Diesel engines have a different mechanism than gasoline engines and require lubricants with specific formulations and grades. 6.7L engines from Cummins are capable of producing up to 450 horsepower and nearly 1,000 lb-ft of torque. To comply with such performance and rugged output, you ought to know what’s best for your engine and how to choose the right oil.

If you’re confused about which engine oil should you be picking, we have compiled a comprehensive list of the 10 best oil for 6.7 Cummins. So you don’t need to do any labour and have all the important info at your disposal. Let’s jump right into it and explore the best oil for 6.7 Cummins.

Best Oil for 6.7 Cummins – Comparisons

ProductOil TypeViscositySpecial FeaturePrice
1. Valvoline Premium Blue SAE Engine OilConventional15W – 40High TBNCheck on Amazon
2. Cummins Onan OilConventional15W – 40Reduced ConsumptionCheck on Amazon
3. Valvoline Premium Blue Extreme Engine OilFull Synthetic5W – 40Thermal ProtectionCheck on Amazon
4. Shell Rotella T6 Synthetic Diesel Engine OilFull Synthetic5W – 40Shear StabilityCheck on Amazon
5. Valvoline MaxLife Technology Motor OilSynthetic Blend10W – 30Extra DetergentCheck on Amazon
6. Mobil 1 High Mileage Synthetic Motor OilFull Synthetic10W – 30Seal ConditionerCheck on Amazon
7. Shell Rotella T5 Diesel Engine OilFull Synthetic10W – 30Low-Ash FormulaCheck on Amazon
8. Delo SAE Synblend OilSynthetic Blend15W – 40Soot DispersionCheck on Amazon
9. Triax Fleet Supreme ESP Synthetic OilFull Synthetic10W – 30Friction ModificationCheck on Amazon
10. Motul Gasoline and Diesel Engine OilFull Synthetic5W – 40Viscous ResistanceCheck on Amazon

Top 10 Best Oil for Cummins 6.7 – Detailed Review

Once you go looking for the oil for your mighty Cummins diesel engine, you’ll be bombarded with a list of products – confusing you to death. We realize how precious your time is and how dear your 6.7 Cummins is to you, so we have reviewed the top 10 engine oils in detail to help you make a solid and informed decision.

1 – Valvoline Premium Blue SAE Engine Oil

The Premium Blue SAE makes one of the most suitable choices for your 6.7 Cummins. It is a conventional oil with a 15W-40 grade that covers a wide range of temperatures.

Formulated for high performance, it ensures proper cleaning of the internal surfaces and complies with all the modern standards of oil manufacturing. It enhances the lifespan and overall performance of your RAM truck.

Features and Benefits

Enhanced Lubrication

Its modern and enhanced formulation ensures perfect lubrication and protection of the engine’s parts. It also boosts the efficiency of diesel engines that have emission treatment done (EGR, or DPF).

Outstanding TBN Retention

Its excellent TBN value neutralizes any harmful acids or contaminants in the engine and maintains the efficiency and composition over long hours of usage.

Ideal Protection of Engine’s Internals

Premium Blue features a Dispersive Polymer Technology (DPT) which offers great soot control, reduces wear, and offers enhanced protection to all the moving parts. Cold startups are perfect and engine wear is also kept to a minimum.


1. Improved fuel economy

2. Better engine cleaning

3. Reduces harmful deposits and wear

4. Enhanced protection of the engine


1. It is prone to slight leakage on the caps

2 – Cummins Onan Oil

Cummins Onan Oil

Developed by the company itself, Cummins Onan oil is put up for sale after rigorous testing and R&D procedures. It has a 5W-40 grade and conventional formulation which offers ideal fuel economy with reduced wear and damage protection.

It is one of the most highly recommended and best oil for the 6.7 Cummins diesel engine.

Features and Benefits

Versatile composition and Viscosity

It comes with a 15W-40 grade that offers near-perfect cold startups and protection in high temperatures. Its composition includes blends and other additives that reduce oxidative stress and wear.

Ideal Formulation

Its ideal formulation offers the best of everything, including performance, fuel economy, and output. With Cummins Onan oil, your engine would have all it needs for on-road and off-road performance.

Suitable Engine Cleaning

To keep the internal parts of the engine clean, Onan oil features a perfect combo of high-quality additives that prevent sludge formation and deposits of harmful chemicals over time.


1. Ideal viscosity for a wide range of temperatures

2. Reduction of mechanical wear

3. Reduced fuel economy

4. Ideal startup and performance


1. Price is slightly on the higher side

3 – Valvoline Premium Blue Extreme Engine Oil

Valvoline Premium Blue Extreme Engine Oil

A great product from a well-known manufacturer, Valvoline. It is one of the highest quality oils for 6.7 Cummins, thanks to its premium fully-synthetic formulation and top-quality additives.

It offers ultimate protection, wear reduction, and superb performance all year long. One of the most recommended oils, Valvoline Premium Blue Extreme gives your Cummins engines what they need the most. 5W-40 grading matches all the viscosity requirements set by the manufacturer and covers all types of weather conditions.

Features and benefits

Specific Cummins Formula

It is highly suited for Cummins engines, especially the 6.7L diesel powerhouse featured in RAMs. It uses a particular formulation and high-quality additives to offer unparalleled protection and performance.

Superb Fuel Efficiency

Needless to say, the fuel efficiency gets improved a lot, thanks to reduced wear, unburnt fuel, and better lubrication of the moving parts of the engine.

Excellent Weather Compliance

The 5W-40 rated viscosity is ideal for the majority of regions and particularly suitable for cold weather. It ensures optimal performance and efficiency, irrespective of where you drive your Cummins-powered trucks.


1. Ideal temperature regulation

2. Optimally controls oxidation and wear

3. Gets rid of sludge and deposits

4. Enhances the lifespan of the drivetrain


1. Packaging and sealing need to be improved for shipment and transport

4 – Shell Rotella T6 Synthetic Diesel Engine Oil

Shell Rotella T6 Synthetic Diesel Engine Oil

Shell doesn’t need any introduction when it comes to POL products. Its oils and lubricants are one of the best and Rotella T6 Synthetic oil is no exception.

With its top-quality formulation, premium additives, and excellent lubrication properties, it offers enhanced performance, lifespan, and fuel efficiency.

For high-performance diesel engines like 6.7 Cummins, Shell Rotella T6 makes one of the best options overall.

Features and Benefits

Enhanced Mechanical Efficiency

Rotella ensures optimal temperature maintenance, reduced friction, and prevents the buildup of contaminants. This excellent fully-synthetic oil ensures that your engine remains fit and offers enhanced efficiency.

Triple protection Plus Technology

This patented technology is specific to shell engine oils and Rotella offers perfect protection for your 6.7 Cummins engine. It prevents the buildup of soot and cleanses the engine regularly.

Prolonged Engine Lifespan

Your Cummins engine would remain as young as ever with the Rotella T6 treatment. It would increase the engine efficiency, as well as the wear reduction for long-term protection and enhanced lifespan.


1. One of the most premium quality lubricants with high-grade ingredients

2. Enhanced engine performance

3. Reduced wear and improved lifespan

4. Offers relatively better fuel efficiency


1. Packaging and labelling are not up to the market standards

2. Can be a bit expensive in comparison to its competitors

5 – Valvoline MaxLife Technology Motor Oil

Valvoline MaxLife Technology Motor Oil

Another great product from the Valvoline family, this time their synthetic blend MaxLife technology oil. Like other Valvoline oils, it offers superior wear protection and an enhanced lifespan for your Cummins diesel engines.

It doesn’t let any sludge or soot from inside the moving parts and covers a wide weather range, all credit to its 10W-30 grade and optimal viscosity over a range of temperatures.

Features and Benefits

Easy Pouring

Its bottle is designed such that you don’t require any funnel or extra equipment to pour the oil into your engine. It also prevents any pour splashing or spouts and makes it easier for the operator.

An Ideal Formula

It has qualities of both conventional and fully synthetic oils and due to added ingredients, it offers enhanced wear protection and keeps friction at a minimum. It is highly suitable for bigger displacement diesel engines like 6.7 Cummins.

Extra Protection

It forms a protective layer over the moving parts, and delicate seals to prevent wear and reduce friction. Over the years of usage and adding up miles to your odometer, Valvoline MaxLife would never let your Cummins engine come to a halt.


1. Has detergent-like properties

2. Prevents oxidation and breakdown

3. Synthetic blend formula offers extra protection

4. Wouldn’t blow a hole in your pocket


1. Not as high quality as a fully synthetic motor oil

2. Packaging can be improved

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6 – Mobil 1 High Mileage Synthetic Motor Oil

Mobil 1 High Mileage Synthetic Motor Oil

Like other Mobil 1 products, the High Mileage Synthetic oil offers superb serviceability. If you own a 6.7 Cummins-powered RAM truck, this oil would make an ideal choice.

It has high-quality additives, premium formula, and 10W-30 grade that offers excellent wear reduction and a wide temperature coverage.

So, whether it’s the efficiency or long-term usability you’re looking for, Mobil 1 High Mileage Motor Oil would suffice your needs.

Features and Benefits

Improved Mileage

Its premium quality ensures that the engine remains healthy in all-weather conditions. It protects from internal friction, keeps the temperature at optimal, and reduces wear. With Mobil 1, your engine would last longer with reduced oil change intervals.

Premium Fully-Synthetic Formulation

Its fully synthetic formula lubricates all the surfaces properly and makes sure there are deposits or buildup of any kind that can affect the performance or efficiency negatively. Mobil 1 is one of the most ideal choices and the best oil for 6.7 Cummins diesel powertrains.

A Lifeline for Cummins Engine

Mobil 1 is one of the preferred choices of performance vehicles and motorsports companies, including NASCAR and Formula 1. With its premium oils like this and high viscosity rating, you could never go wrong with your Cummins engine.


1. Extra seal conditioner

2. Premium additives in the fully synthetic formulation

3. Excellent wear protection for high-performance engines

4. Extended lifespan of your engine, especially Cummins diesel

5. Good temperature protection and output


1. Available only in small volumes and containers.

7 – Shell Rotella T5 Diesel Engine Oil

Shell Rotella T5 Diesel Engine Oil

Another great product from Shell, Rotella T5 is specifically formulated for high-performance diesel engines and it delivers on all fronts. Fully synthetic and featuring premium additives, there’s nothing your Cummins needs more than this motor oil.

A versatile 10W-20 grade and ideal lubrication keep the engine running all year long, irrespective of the weather conditions, and makes sure that the lifespan of your motor is enhanced with optimal cleaning and wear reduction.

T5, just like Rotella T6, is one of the highly recommended and best oil for 6.7 Cummins engine.

Features and Benefits

Long-term Serviceability

Manufactured according to industry standards, it is one of the best and most long-lasting oils that you could get. The company recommends longer change intervals of 5,000-7,000 miles with Rotella T5. It is best that you replace the engine oil filter along with oil as well, for better engine protection.

Ideal Engine protection

Featuring the same Triple Protection Plus technology, it protects the inside of your engine like a guardian. It optimally lubricates all the surfaces which prevent friction and wear of the moving parts.

Highly Compatible and Diesel Friendly

It has a low ash composition and features premium additives that protect the diesel particulate filters and catalytic exhaust parts for a longer duration. Not just your routine engines, it is well-suited for rugged powerhouses like 6.7 Cummins diesel.


1. Much better fuel efficiency

2. Optimal temperature maintenance

3. Protects internal parts from corrosion and wear

4. Wide range of compatibility and applications for diesel engines


1. Its casing and cap can crack easily while transporting and cause leakage.


8 – Delo SAE Synblend Oil

Delo SAE Synblend Oil

Another synthetic blend oil on the list, Delo Synblend oil has a versatile 10W-40 viscosity rating and is well-known for prevention of corrosion and soot buildup.

The maintenance also becomes easier with your diesel engines, and it is regarded as a suitable choice for 6.7 Dodge engines.

Features and Benefits

Unique Composition

It features a patented Isosyn technology for improved performance and efficiency. It sets high standards in terms of serviceability and protection against wear.

Functional Formulation

Despite being a synthetic blend oil, it still offers premium lubrication and prevents corrosion in high-mileage diesel engines, particularly 6.7 Cummins.

Ideal Protection

It has a detergent-like property which is ideal for corrosion resistance and protection of other mechanical components, like turbochargers. It is also known for reducing soot deposits and removal of harmful oxidative chemicals.


1. Unique patented technology

2. Compatible with the majority of diesel powertrains

3. Better fuel economy

4. Aggressive removal of harmful deposits


1. Packaging and container quality are substandard

9 – Triax Fleet Supreme ESP Synthetic Oil

Triax Fleet Supreme ESP Synthetic Oil

Triax may not be as popular as Shell or Valvoline but its premium chemistry and formulation offer superb engine protection, efficiency, and long-term serviceability.

It enhances the functioning of your 6.7 Cummins engine, reduces friction, and offers ideal lubrication for all surfaces. If you’re looking for an oil with 10W-30 grade and fully-synthetic formulation in the budget, Triax Fleet ESP may be your best choice.

Features and Benefits

Immaculate Functioning and Protection

It features a new VI stabilising formula that offers high-temperature stability and resistance to degradation. It also has additional dispersing agents that prevent the deposition of any harmful agents and remove previous sludge or contaminants.

Unparalleled Compatibility

It is compatible with a range of diesel engines but is ideal for 6.7 Cummins as well. It offers superb performance and high protection against wear and deposits, especially in diesel engines.

Enhanced Fully Synthetic Formulation

Not only does it have a premium fully synthetic formula, but it also has additional ingredients like the friction modifier that ensures optimal lubrication and temperature resistance. It is one of the most premium and best oil for 6.7 Cummins that you could get right now.


1. New fully synthetic formula with premium additives

2. Excellent economy

3. Longer replacement intervals

4. Versatile compatibility


1. Limited availability

10 – Motul Gasoline and Diesel Engine Oil

Motul Gasoline and Diesel Engine Oil

It’s a newer offering from the manufacturer and well-suited for all the diesel engines, especially 6.7 Cummins powertrains. Formulated using the latest techniques and premium additives, it is ideal for long-term usage and enhanced output.

It is great for better fuel economy, corrosion resistance, and performance of diesel engines. No need to look further than the Motul Gasoline fully synthetic oil, ideal for both gasoline and diesel.

Features and Benefits

Enhanced Fuel Economy

You get a much better fuel economy with Motul, thanks to its better lubrication and consumption of unburnt fuel. Fuel consumption is considerably reduced and you get a better economy in the longer run.

Better Sludge Removal and Cleansing

It penetrates even the stubbornest of sludge and soot deposits and gets rid of them. Prevents corrosion and gets rid of oxidative chemicals inside the engine.

Temperature Resistance

Oil pressure and temperature are maintained optimally, no matter how harsh the driving conditions are. A thin layer offers optimal resistance to wear and friction, thanks to the superior lubricating properties of the Motul, one of the best oil for 6.7 Cummins.


1. Good viscosity rating and maintenance over time

2. Enhances fuel economy

3. Reduces harmful deposits from the engine, prolonging life and enhancing performance


1. Not so great in packaging and is not specifically designed for diesel engines. It is universal, for both diesel and gasoline powertrains.

How to Really Choose the Right Engine Oil for 6.7 Cummins?

To have your Dodge engine perform at its finest, you need to feed it the best oil for Cummins 6.7. An engine needs the right type and grade of oil for it to have optimal lubrication, performance, and ideal fuel economy. Let us help you choose the right engine oil for the 6.7 Cummins diesel powertrain.

Manufacturer Guidelines

No matter how good a salesman might sound, you should never jump to conclusions when it comes to choosing engine oil for your car. To choose the best oil for 6.7 Cummins, you should check the manufacturer’s recommendations and pick the right type and grading of oil. For that purpose, consulting the owner’s manual is the easiest and most suitable option.

Oil Grade

SAE has divided oils into different grades, based on viscosity grading. It is crucial to consider the grade of oil as it has to perform in the coldest of winters and hottest of summers.

For your 6.7 Cummins, 10W-30 is the recommended oil grade and must be preferred over the other grades

Oil Formulation and Chemistry

Fully synthetic oils are the most premium engine oils available on the market and if you’re looking for the best oil for 6.7 Cummins, it most definitely should be fully synthetic oil.

It has no remnants, or contaminants from the refining process and offers optimal output with fuel efficiency. It is important to prefer fully synthetic over conventional and synthetic blend oils.

Additional Additives

Having additional additives, such as friction reducer, triple protection plus, and other patented technology enhances the performance and reduces wear inside the engine.

Almost all fully synthetic oils come with premium additives that offer these exceptional qualities and prolong the lifespan of your 6.7 Cummins diesel engine.

Types of Oil for 6.7 Cummins

As we have already discussed the different types of oil based on formulation and viscosity grading, there’s more to it than an owner must know, to make the best choice while choosing the engine oil.

Cummins engines require different types of oils based on their calibration and configuration, particularly according to their model years. So you must know those types of oil for 6.7 Cummins as well.

Type of Oil for 6.7 Cummins (2014) SAE 5W-40 is the recommended oil type for the 2014 6.7 Cummins diesel engine, based on its engine power and output.

Type of Oil for 6.7 Cummins (2017) With a slight improvement in torque and power, you can choose SAE 15W – 40 or SAE 5W – 40 oils in your 2017 6.7 Cummins.

Type of Oil for 6.7 Cummins (2018) To get maximum output from your 2018 Cummins engine, 15W-40 makes an ideal choice. It has almost similar power figures as compared to the 2017 version of the engine.

Type of Oil for 6.7 Cummins (2019) With nearly 1000 lb-ft torque and 400+ horsepower, 2019 year is the most powerful 6.7 Cummins engine to date. You should ideally use SAE 10W – 30 or SAE 5W – 40 in your latest RAM truck with this powertrain.


Q1- How often should I change engine oil in my 6.7 Cummins engine?

As per the manufacturer’s guidelines, you should change the oil every 5,000 miles or 6 months, whichever comes first.

Q2- Which is the best oil filter for my RAM 6.7 Cummins engine?

You ought to change the oil filter at every interval, as it prevents contamination and enhances the oil life. The ideal choice for your 6.7 Cummins engine is aFe Power EcoDiesel Oil Filter.

Q3- What is the Oil Capacity of 6.7 Cummins?

Your 6.7 Cummins has an oil capacity of 11 litres or 12 quarts.

Q4- How much does it cost to get an oil change in 6.7 Cummins?

It would cost you in a range of $80-120 for getting the oil changed in your Cummins diesel engine, including tax and labour charges.

Final thoughts

If you’re looking for the best diesel oil for 6.7 Cummins, you should never compromise on the quality and promise of the product.

We have put together a comprehensive piece to help you get all the info and make an informed decision. You just have to find the vehicle’s information and powertrain specification after checking out our recommendation, and you’d never look back.

Based on our extensive research, Valvoline Premium Blue Extreme Engine Oil turns out to be the overall best oil for 6.7 Cummins. It has premium qualities, wide temperature coverage, excellent fuel economy, and reduced engine wear. It is the best treatment you could get for your beloved RAM truck.