Shell Rotella t6 vs t5

You have a big decision to make. Which engine oil should you put in your car? Do you go with the tried-and-true Rotella T6 or experiment with the new Rotella T5?

In this article, we’ll compare the two oils and help you decide which is the better choice for you. We’ll try to make a comparison between Rotella T6 VS T5 so that you can choose the right one for your vehicle. So, let’s dig into this article.

A Comparison between Rotella T6 VS T5

Undoubtedly both these oils are great to use. But you need to pick just one. This is why, we will try to make a comparison between Rotella T6 VS T5. It will surely help you to choose the right one for your vehicle.


Though both oils are designed for heavy-duty diesel engines, but they have some differences. The main difference between Rotella T5 and Rotella T6 is their viscosity.

Viscosity is a measure of a fluid’s resistance to flow. The higher the viscosity of a fluid, the thicker it is, and the more resistance it has to flow. Rotella T5 is a 5W-40 viscosity oil which means it has a low viscosity, meaning it has a thinner consistency and will flow more easily than Rotella T6. On the other hand, Rotella T6 is a 15W-40 viscosity oil, meaning it is thicker and has a higher viscosity.

The increased viscosity of Rotella T6 allows it to better protect an engine’s moving parts, especially at high temperatures. It also helps to reduce oil consumption and prevents sludge buildup. Rotella T5 is better for engines that don’t require the extra protection of a higher viscosity oil, such as older engines or those that operate in cooler temperatures.

Rotella T5 and T6 are both excellent synthetic motor oils, but they have different viscosity. Rotella T5 is a 5W-40 viscosity oil and is better for engines that don’t require the extra protection of a higher viscosity oil. Rotella T6 is a 15W-40 viscosity oil and is better for engines that are subjected to extreme temperatures and need the added protection of a higher viscosity oil.


When it comes to additives, both Rotella T6 and T5 have a lot in common. They both have detergents, dispersants and other additives that keep the engine running smoothly. However, there are a few key differences.

For starters, Rotella T6 has a higher content of ZDDP, or zinc dialkyldithiophosphate. This additive helps protect engine parts from wear and tear, making it a good choice for high-performance engines. Rotella T5 doesn’t have as much ZDDP, which could make it less effective in protecting your engine.

Rotella T6 also contains an additive called MPDO, or methylphenidate. This additive is designed to help control emissions and improve fuel economy. It’s not found in Rotella T5.

Finally, Rotella T6 has an additive called PEA, or polyethylene glycol. This additive helps keep the oil from thickening in cold weather, making it a good choice for colder climates.


Both Rotella T6 and T5 are compatible with cars that require the use of diesel oil. The Rotella T6 is designed to be used in high-performance engines and meet the standards of both Cummins and Detroit Diesel, while the Rotella T5 is designed to be used in both diesel and gasoline engines.

The Rotella T5 is also designed to work with modern emission systems, making it a great choice for recent model vehicles.

In terms of compatibility, the Rotella T5 has an advantage over the Rotella T6 as it can be used in most modern engines and vehicles, while the T6 can only be used in specific models.

However, it’s important to note that if your car requires a synthetic oil, then you should avoid using either of these oils as they are not synthetic based.


Talking about the efficiency of Rotella T6 VS T5, this is one of the most important factors to consider when it comes to choosing a motor oil. The higher the efficiency, the better it will perform in high-stress situations such as extreme temperatures and high-performance racing.

Rotella T6 is rated at 10W/30 and offers improved fluidity in colder temperatures while also providing more protection against engine wear due to its higher viscosity rating. The oil also contains a higher concentration of detergents than most other synthetic oils, which helps keep engines clean and running efficiently.

On the other hand, Rotella T5 has a 15W40 viscosity rating and is ideal for engines that are operating in extreme temperatures. Its formulation includes additives to help reduce oxidation and extend engine life, but its lower detergent content means that it may not be as effective at keeping engines clean over longer periods of use.

Oil Change Intervals

When it comes to oil change intervals, they are not exactly the same for both products. With Rotella T6 you should wait up to 15,000 miles before changing the oil, while with Rotella T5 you should be looking at changing the oil in half that distance.

The bottom line is that if you are looking to get more mileage out of your engine, then you’ll want to use Rotella T6. Not only will it keep your engine running more efficiently, but you won’t be spending money on oil changes as often.


When it comes to making the decision between Rotella T6 and T5, cost is certainly going to be a factor. Let’s take a look at the cost comparison between the two.

Rotella T6 is significantly more expensive than T5, because it’s a synthetic-blend motor oil. The synthetic base means that it’s more efficient than conventional motor oil, which translates into better fuel economy and longer engine life. That being said, if you are looking for an affordable option then Rotella T5 is a great choice.

On the other hand, if you want a longer lasting performance then Rotella T6 is your best bet. The synthetic blend will provide better protection against engine wear and tear, allowing your engine to last much longer than its mineral-based counterparts. You’ll also save on fuel costs due to its excellent oil efficiency rating.

So although it may cost more upfront for Rotella T6, in the long run you’ll save money due to its superior performance and efficiency ratings compared with traditional motor oil like Rotella T5.

Rotella T6 VS T5- The Winner

So, now that you know the key differences between Rotella T6 and T5, you’re probably wondering which one is the better option.

The answer is that it really depends on what your needs are. For example, if you want an oil that will protect your engine and perform in extreme temperatures and give a long oil change interval, then go for Rotella T6. On the other hand, if you want an oil that won’t break the bank, then go for Rotella T5.

No matter which one you choose, both oils have excellent protection for your engine and will keep it running like new for a long time. And with proper maintenance, either one of these lubricants can make your engine run efficiently with minimal wear and tear.

Frequently Asked Questions

Is Rotella T5 good for diesel engines?

Yes, Rotella T5 is a good oil for diesel engines. It is specially formulated with a low-ash formulation to help protect and extend the life of diesel engines. It also helps reduce emissions and provides better fuel economy.

Is Rotella T5 good for Duramax?

Yes, Rotella T5 10W-30 is an excellent oil for the Duramax diesel engine. It provides superior protection against wear and corrosion, and it meets the GM specification for the Duramax engine. Additionally, it has excellent cold-temperature performance, which helps ensure that the engine starts quickly and runs smoothly in cold weather.

How many miles is Rotella T5 good for?

Rotella T5 provides  excellent wear protection, well beyond the common recommended oil drain interval of 50,000 miles demonstrated through oil analysis during millions of miles of field testing.

Why is Rotella T6 so good?

Shell Rotella T6 reduces ash, phosphorus, and sulfur levels to prevent blocked DPFs and increase overall efficiency. Compared to other 5W-40 formulas, Shell Rotella T6 shows 34% better wear performance.

Is Rotella T6 a true synthetic?

Yes, it is a full synthetic motor oil that features exclusive Triple Protection Plus technology, formulated with fully synthetic base oils plus advanced additives to protect against wear, deposits, and oil breakdown.

Final Thought

In the end, it all boils down to what you’re looking for in an engine oil. If you want a bit more performance and don’t mind sacrificing a bit of fuel economy, Rotella T6 is a great choice. But if you want an engine oil that’s compatible with a wide range of engines and offers great fuel economy, go with Rotella T5.

In this article, we try to make a comparison and also make a decision which is better to pick between Rotella T6 VS T5. Hopefully, it will be helpful for all of you to get am overall idea. Thank you all.


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