rotella t6 5w40 vs 15w40: What’s the difference?

The Rotella line of oils has a fairly consistent history of quality and performance.

Over the years, however, the Rotella T6 5W-40 and Rotella T15 15W-40 have started to become more popular.

These two popular engine oils have been developed by  Royal Dutch Shell to meet the needs of different vehicle needs.

Below is a table of comparison between rotella t6 5w40 vs 15w40:

Best forMotorcycle, Car, TruckFord wss
Improved piston cleanliness to industry standard
Better low temp flow
Better drain intervals
Breakdown resistance under high temp
Shell 10 year or 300K mile protection
Shell10 year or 500K mile protection
Prevent engine wear

Shell Rotella T6 15W40 and 5W40– (quick overview)

1. Shell Rotella T6 Full Synthetic 15W40 Diesel Engine Oil

Shell Rotella T6 Full Synthetic 15W40 Diesel Engine Oil

Shell Rotella T6 Full Synthetic 15W40 Diesel Engine Oil is a high-quality engine oil with a 5-star rating. It has been designed to provide the best performance in extreme conditions, particularly in hot and humid environments.

This oil is manufactured using premium base oils and synthetic technology. It has proven to be an excellent choice for diesel engines. It provides superior protection against wear, corrosion, foaming, and deposits.

The oil also comes with an anti-foam additive, making it suitable for use in all types of turbocharged or supercharged diesel engines, including those with variable geometry turbos.

Reduce Camshaft Friction

Shell RotellaT6  synthetic 15w40 engine oil maintains optimal shearing force within the cylinder and keeps lubricant film thickness at its optimum level so that it does not reduce the engine durability of your vehicle.

It will help the motor rotate at low temperature without tiring out the engine components, thus saving time for oil changes.

As a result, fuel economy increases reduce frictional loss within every critical part of engines and leaves behind less friction on cams, thereby reducing wear-and-tear stress.

Reduce Camshaft Friction

Shell Rotella synthetic engine oil is an advanced low ash formulation that will reduce exhaust emissions and fuel consumption of your vehicle.

Environmental protection has become a priority for all motor vehicle manufacturers because there are several ways they can improve the performance of their engines in the future.

At the same time, this oil reduces fuel consumption and smoke emission by gradually lowering combustion temperature, resulting in no more harmful contaminants released into the air.

Lubricant to last long

Shell Rotella 5W-40 has world-class superior lubricants that make it the best in the market and offer outstanding performance for your car engine.

It is recommended for every kind of modern city cars, SUVs & vans with engines around 2 liters displacement such as VW, Seat, Alfa Romeo, and many others.

Excellent oxidation protection

Shell Rotella 5w-40 engine oil has excellent protection against wear and oxidation so that it can protect your engine from harmful contaminants.

Reduces engine friction

Shell Rotella 5W-40 oil reduces engine wear by reducing fuel consumption and helps in saving your vehicle’s engine. It also improves the fuel efficiency of the vehicle engines.

It contains all additive packages of synthetic motor vehicles fuel economy, engine performance, and protection oil to preserve all of its benefits.

2. Shell Rotella T6 Full Synthetic 5W40 Diesel Engine Oil

Shell Rotella T6 Full Synthetic 5W40 Diesel Engine Oil is high-quality engine oil that is suitable for use in all diesel engines.

It  has been engineered to provide the ultimate in performance, which means it will protect your engine and help improve fuel economy

It also  meets European and American standard API SN and ACEA A3/B4 requirements.

This product helps your engine work at peak performance levels by preventing wear, increasing fuel efficiency, reducing friction, and improving performance while lowering emissions.

Fuel efficiency

Shell Rotella T6 diesel engine oils improve the fuel economy of engines used in heavy-duty diesel engines, where fuel economy is a key concern.

According to their official data, it has the capability of more than 1.5% fuel economy capability.

Improved deposit control

Advanced multi-functional dispersant additives in combination with synthetic base oils provide an enhanced level of protection against the effects of soot, dirt, and other contaminants.

Emissions system compatibility

Shell Rotella T6 Full Synthetic 5W40 Diesel Engine Oil is a full synthetic diesel oil well suited for high load engines where nitrile sludge deposits are common;

It meets all Euro 4 emission requirements. Shell Rotella T 6 Full Synthetic 20W-50 diesel engine oil has minimal viscosity change required for full diesel engines.

The oil remains synthetic at temperatures of up to 150°F (65.6oC), which complies with all US EPA specifications for motor oils under low-temperature protection requirements.

Maximum Engine Protection

Shell Rotella T6 Heavy Duty Steel engine oils, compared to other motor oils, offer full protection against wear, sludge, and corrosion with improved thermal stability.

They provide excellent protection for oil-cooled engines – offering the ultimate performance without sacrificing economy at all speeds.

Oxidation Protection

Shell Rotella engine oils have low-level oxidation, which enables them to perform at temperatures up to 225°F (107oC) in a fully synthetic base oil formulation for heavy-duty diesel where fuel economy, protection against wear, sludge, and corrosion are of key importance

Shell claims that Shell Rotella T6 full synthetic 15w 40 provides better protection against harmful wear and corrosion compared to previous generation API CJ-4 oils at all temperatures up to 200°F (93oC).

This means it will perform well for elevated temperature operation as opposed to older formulation oils which would not have offered full protection in engines that regularly achieved high temperatures.

Rotella T6 5w40 vs 15w40: which is better?

5w40 is a premium engine oil, which means it has been specially formulated to provide the best performance in high-performance engines.

15W40 is industrial engine oil, which means it has been specially formulated for applications subjected to higher loads and/or greater temperatures than those encountered in standard automotive engines.

In general, 5w40 outperforms 15W40 because of its higher viscosity grade. A high viscosity grade indicates that the oil can flow easily when cold and provides more protection against wear and corrosion when hot.

Is synthetic oil worth using instead of regular motor oil?

In short, synthetic oil is worth it to use in your car. Synthetic oil provides better performance, lower wear and tear, and a longer lifespan for your engine.

The benefits of using synthetic oil are:

  • Higher efficiency due to the fact that it doesn’t have the same level of friction as regular motor oil does when moving through an engine’s parts.
  • Lower fuel consumption due to less friction in the engine.
  • More protection against corrosion caused by rust and oxidation from being in contact with oxygen.
  • Longevity of synthetic oils is much longer than regular motor oils, which makes them more cost-effective over time because you don’t need to replace them as often.

Relevant posts:

closing thoughts

Both of these  premium quality oil will provide you with maximum protection from wear and corrosion while reducing friction and heat at the same time.

They also protect against sludge, varnish, and carbon build-up, ensuring smoother acceleration, reduced smoke output, increased horsepower, better fuel efficiency, improved thermal stability, and longer life of other key components like spark plugs.

Choose the one you think is suitable for your vehicle engine.

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Mahir Ahmed


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