5 Best Oil For 5.9 Cummins In 2021 [Thoroughly Reviewed]

The motor oil inside an engine does more than just providing energy. It is undoubtedly the life-giving component that handles lubrication, cooling, friction reduction, corrosion protection, etc. 

But only a good motor oil can help the engine to do so. Cheap motor oil can cause the health of the engine to deteriorate instead of improving. 

The worst part is, there are so many cheap and low-quality motor oils available in the market that getting manipulated into buying one is not surprising. 

5.9 Cummins is an extremely durable engine. If you treat it with proper care and regular oil change, it will outlast your trucks’ body. But using a cheap engine oil is only going to harm it.

After thorough research, we have selected five of the best oil for 5.9 Cummins engine that will not let you or your 5.9 Cummins down. Our top favorite among these oils is the Valvoline premium Blue motor oil.

It’s the ultimate motor oil that will prolong the health of your engine and give it the kick it needs to roar on the road!

Let’s take a look at the other products and what they bring to the table!

5 Best Oil For 5.9 Cummins: Comparison Chart

 

Product Name Oil Type  Viscosity  API certification 
Valvoline Premium Blue Synthetic  SAE 15W-40 CK-4, CJ-4, CI-4, CI-4 Plus 

Royal Purple Duralec Super Oil

Synthetic SAE 15W-40 CK-4
Shell Rotella T6 Diesel Engine Oil Synthetic SAE 15W-40 CK-4, CJ-4, CI-4, CI-4 Plus
Schaeffer Manufacturing Co.  SynShield Engine Oil Para-synthetic SAE 15W-40 CK-4
Mobil 1 Delvac 1300 Super SAE Motor Oil Synthetic SAE 15W-40 CK-4

5 Best Oil For 5.9 Cummins Reviews

1.Valvoline Premium Blue

The Valvoline premium blue can be considered as the ultimate motor oil for your 5.9 Cummins. The engineers at Cummins and Valvoline came together and created this oil that fits all the criteria and provides the utmost care and protection to the engine. 

Features:

  • Outstanding Fuel economy: Fuel economy is the most important criterion if you are always on the road. Other oils in the market offer a good fuel economy but the Valvoline premium blue just takes the cake.It offers 10,000 miles extended oil drain interval in all Cummins engines. And due to the extended drain intervals, it offers a 3% fuel economy in trucks.
  • Excellent Lubrication: Due to its synthetic components, the Valvoline premium blue never changes its viscosity when the temperature changes.The synthetic base ensures your engine starts faster than ever even in freezing temperatures. It’s completely resistant to the extremely high temperature of a turbocharger.
  • No More Turbo-coking: As we already said, the Valvoline premium blue is resistant to heat thanks to its synthetic formula. It doesn’t solidify or evaporate when the turbocharger becomes extremely hot.Therefore, the blockage caused by oil deposits on the turbocharger doesn’t happen when you use this oil.

Pros 

  • Statistically proven 3% fuel economy improvement 
  • 10,000 miles oil drain intervals 
  • Outstanding lubrication and protection 
  • DPT protects and resists corrosion

Cons 

  • The texture is thinner than regular motor oil

2. Royal Purple Duralec Super 15W40 Oil

The Royal Purple Duralec Super motor oil is a heavy-duty synthetic oil formulated to fuel powerful engines like the 5.9 Cummins. Granted it is a bit costlier than the average motor oil in the market, but its advanced formulation and top-notch performance make the price tag justifiable. 

Features:

  • Synthetic Formula: When it comes to the ideal 5.9 Cummins oil type, almost everyone prefers synthetic oil. Synthetic oils provide better protection, better lubrication and are resistant to extreme weather changes.The synthetic formula of the Royal Purple Duralec Super offers top-notch oxidation stability. Low volatility ensures that there is no change in viscosity when the turbocharger is extremely hot or when the weather is freezing outside.
  • Great Protection: Most of the wear in engines happens during the start. If the oil you are using is not lubricating enough or has thickened, you will face a hard time trying to start your truck. And you will end up harming your 5.9 Cummins more than you can imagine.But with the Duralec Super and its low volatility, high oxidation stability formula, you will no longer have to worry. Because even in freezing temperatures, it provides amazing lubrication to keep the engine smoother and safer.Packed with nourishing oil additives, the Duralec Super ensures engine protection even when it’s not running. Once the engine is off, the additives protect the metal parts of the engine from acid corrosion and rust by sticking to them.
  • Better cleanliness: The Royal Purple Duralec super motor oil doesn’t evaporate, thicken or leave deposits on the valves due to its synthetic formula.And its advanced formula fills the gap between cylinder walls and pistons in the engine which reduces exhaust emissions significantly. The oil additives in the motor oil form a strong oil film which keeps the engine clean and free of deposits.

Pros 

  • High oxidation stability ensures stable viscosity 
  • Formulated with additives to keep the engine acid corrosion and rust-free 
  • Compatible with other types of motor oils 
  • Decreases exhaust emissions 

Cons

  • The Duralec super is quite expensive

3. Shell Rotella T6 Full Synthetic SAE 15W-40 Diesel Engine Oil

The Shell Rotella T6 motor oil offers the ultimate balance between protection, lubrication, and money. If your motor oil changes its viscosity regularly, then don’t worry. Grab one Shell Rotella full synthetic engine oil and you will no longer have to feel disappointed by your engine oil.

Features:

  • More Stability And Less Volatility: The full synthetic formula of the Shell Rotella motor oil makes it much more stable and low volatile than the other motor oils in the market.Due to its low volatility, it offers a much better fuel economy and lower oil consumption rate with an extremely reasonable price tag. Its stable formula is so popular that many people use it on their motorcycles and even on gasoline cars.
  • Excellent Wear Protection: Since it’s fully synthetic, this oil reaches the critical lubrication points of the engine at the start at a much lower time and can save up to 90% of engine wear during the start. As the 5.9 Cummins is a powerful engine where the most engine wear happens at the start, this oil is exactly what you need.The low volatility and high oxidation stability full synthetic formula make it perfect for use during freezing temperature as its viscosity remains the same.
  • 70% More Oxidation Protection: The Shell Rotella full synthetic motor oil is API CK-4 certified. But that’s not the only part. It is formulated to meet and exceed the CK-4 specifications by a large margin.Its advanced formula provides an 85% improvement in engine corrosion, 50% more engine wear protection, and 70% more oxidation protection than required. So if you use this oil on your 5.9 Cummins, not only will it perform great, it will also stay great for a long time.

Pros 

  • The full synthetic formula provides low volatility and high oxidation stability 
  • Excellent during cold weather 
  • Provides a slower oil consumption in 5.9 Cummins 
  • 50% more engine protection than API requirements 

Cons 

  • The engine might get dirtier than usual

4. Schaeffer Manufacturing Co. SynShield Engine Oil

When it comes to trustworthy lubricant brands, Schaeffer is a name that everyone trusts. It’s been around for nearly 200 years and its reliable formula has never let anyone down. The Durability advantage engine oil by Schaeffer is proof of this statement. 

Features:

  • Para-synthetic Formula: The Schaeffer SynShield is a para-synthetic motor oil. While many think they should only use a full synthetic oil in their 5.9 Cummins, we do not agree with this thought.Due to the para-synthetic formula of this oil, it offers a lower oil consumption rate and an improved fuel economy. The para-synthetic formula stops the oil from thickening which offers a better engine performance as well.
  • Amazing Wear Protection: Because of the para-synthetic components of this engine oil, it reaches critical lubrication points even in cold and freezing temperatures. This reduces the engine wear on freezing days significantly.Formulated with micron moly friction modifiers, this oil creates a strong film between metal parts to avoid friction. This reduces engine wear and protects the valve, pistons, and cylinders of the engine from wearing down each other. Its para-synthetic formula offers 85% less engine wear than a regular API CK-4 motor oil.
  • Better Soot Control: Made with great oil additives, this oil has an excellent cleaning ability and offers great protection against oil deposits in the engine.The soot dispersants protect against soot overloading in the engine and offer a 77% better soot control than required.

Pros 

  • The para-synthetic formula keeps the engine protected 
  • Low oil consumption rates offer a better fuel economy
  • Offers 85% less engine wear than regular oils 
  • Provides 77% better soot control 

Cons 

  • Not a full synthetic formula

5. Mobil 1 Delvac 1300 Super SAE Motor Oil

The Mobil 1 Delvac 1300 Super motor oil is a heavy-duty oil that is known to provide ultimate protection against engine wear. Its synthetic blend formula offers the best performance within a reasonable price tag. 

Features:

  • Extended Oil Drain Intervals: The synthetic blend formula of the Mobil 1 Delvac 1300 super motor oil offers excellent oxidation stability. This means it will not thicken, and lose its chemical properties over time. This gives you a long time to drain and change the oil of your 5.9 Cummins.
  • Outstanding Wear Protection: Hydro-processed base stocks and advanced oil additives in the formula ensures this oil stays the same in cold weather. So, when you start your truck at freezing temperature, it’ll reach the critical lubrication points and provide a smoother, safer, and faster cold start-up for the engine. 
  • Similar Viscosity Through The year: Motor oils need to maintain similar viscosity even when the weather changes to maintain optimal performance. As you know, the engine wears out the most at the start. With increased and extremely hot weather, the viscosity decreases.And with freezing temperature the viscosity increases. But with the Delvac 1300 engine oil, you don’t need to face this issue as its viscosity remains unchanged all year.

Pros 

  • Perfect for cold and freezing temperatures 
  • High oxidation stability and low volatility ensures optimal performance 
  • Controls soot build-up in an excellent way 
  • Provides longer gasket life and better fuel economy 

Cons 

  • It’s not a full synthetic formula 

Best Oil For 5.9 Cummins: Buyer’s Guide

To choose the best oil for your 5.9 Cummins, you have to make sure your pick is ticking all the important boxes. Here are the factors to keep in mind while looking for the ideal motor oil for your reliable workhorse.

Oil Viscosity

Oil viscosity is the most important factor when it comes to choosing the right oil for your 5.9 Cummins. The right grade of oil decides whether your 5.9 Cummins will outlast your truck or there’ll be a drastic decrease in the performance. 

The right grade of oil refers to its viscosity. Viscosity refers to the flow resistance of the oil. Oil viscosity can change dramatically depending on the temperature. The ideal viscosity or oil grade for your 5.9 Cummins is 15W-40. The oil grade was developed by the Society of Automotive Engineers (SAE). 

15W-40 motor oils are multigrade engine oils. They work perfectly in both freezing and burning temperatures without messing with the viscosity of the oil. 

All the recommended motor oils in our list have “SAE 15W-40” written on them. This means they are the right grade of oil for your 5.9 Cummins as decided by the SAE.

Oil Type

There are three types of engine oils in the market. Conventional oil and synthetic oil are the most commonly used. Synthetic oils are better than conventional oils for multiple reasons.

The turbocharger at the engine’s cylinder is important for a fuel-efficient engine. Most diesel engines and 5.9 Cummins these days are built with one to add power to the engine when required.

If you are putting a lot of pressure on the engine with a heavy load, then the turbocharger will get hotter than usual. Once you turn off the engine and cut off the oil flow, the oil left inside the hot turbocharger will start to boil. 

If the oil you’re using has high volatility, then it will evaporate and leave deposits on the turbocharger. The deposits will hinder regular oil flow on the turbocharger leading to “turbo-coking”. A process where the oil flow in the turbocharger is completely blocked. 

Conventional oil has high volatility. But this is not the case with synthetic oils. 

So, If the oil is thickened due to the freezing temperatures, then your engine will need to provide more energy at the start. Which will lead to faster health deterioration for the engine. 

Conventional oil thickens in freezing temperatures. Whereas, synthetic oils don’t and their viscosity remains the same throughout the year. 

So, if you live in an area with extreme weather conditions, or if you drive all over the country, opt for synthetic oil to achieve maximum performance while ensuring the engine’s health.

Ash Content 

Ash content refers to the deposits on the valve of the engine which can cause valve damage and even burning. Ash content can cause severe build-up, and decrease the performance of the engine entirely. 

It is recommended by Cummins that the motor oil used on your 5.9 Cummins should have a low ash content. They recommend using an engine oil with maximum ash content of 1.85%. Any higher than this will ruin your 5.9 Cummins drastically.

Any motor oil that is API CI-4, CK-4 certified has a low ash content.

Frequently Asked Questions

Q: How often should you change the oil in a 5.9 Cummins?

Ans: Proper care for your 5.9 Cummins includes routine oil changes. It ensures maximum wear protection without harming the engine. The oil change intervals vary between the different versions of 5.9 Cummins. For a 5.9 Cummins 12 valves, you should change the oil every six months or 6,000 miles. For 5.9 Cummins 24 valves, change the oil after 7,500 miles or every six months. 

Q: Do I Need to Add Oil Additives?

Ans: Unless you are pouring cheap and low-quality motor oil into your truck, there’s no need to use oil additives. Granted, additives add and enhance the performance of the engine and the fuel, but all if not most API-certified motor oils come with the required additives.

Q: How Much Oil Does A 5.9 24 Valve Cummins Take?

Ans: All 5.9 Cummins oil capacity is the same. They all have a capacity of 12 quarts. This includes the oil filter which has a capacity of 1 quart. A 5.9 Cummins with 24 valves has an oil capacity of 11 quarts and 1 quart in the oil filter.

Final Words

With our 5 best oil for 5.9 Cummins review, your engine will perform great and last for a long time. 

Our overall favorite among these five oils is the Valvoline Premium Blue. Endorsed and created as the perfect companion for Cummins engines, the Valvoline premium blue motor oil is best at what it does. It’s impossible to find an engine oil similar to this within its price tag. 

After seeing its low volatility, low ash content, and oxidation resistance, we can consider it as the best oil for Cummins 5.9 engine. 

However, many customers do not agree with Cummins. If you don’t like the Valvoline premium blue, opt for any other oil from our list. Each of these oils is equally great and has our recommendation for 5.9 Cummins.

Leave a Comment