Best Oil for Duramax Engine

Duramax is a range of high-performance engines developed by Isuzu and GM, for the Dmax series and other vehicles. These beasts are juggernauts, employed in commercial vehicles, and trucks. To ensure optimal functioning, longevity, proper …

best oil for duramax engine

Duramax is a range of high-performance engines developed by Isuzu and GM, for the Dmax series and other vehicles. These beasts are juggernauts, employed in commercial vehicles, and trucks.

To ensure optimal functioning, longevity, proper performance, and temperature maintenance, one ought to use high-quality engine oils and lubricants in these Duramax engines.

High-performance diesel engines work differently than gasoline ones, and you must use the right type and grade of oil for Duramax engines to work perfectly. There are different varieties of oils available in the market and you must pick the best oil for Duramax Engine.

To help you make the right decision and pick the best oil for Duramax engine, we’ve scripted a comprehensive guide;

Best Oil For Duramax Diesel Engines – Comparison

ProductOil TypeViscositySpecial FeaturePrice
Shell Rotella T6 Synthetic Engine OilFull Synthetic5W-40Low-Ash AdditivesCheck on Amazon
Liqui Moly Premium Synthetic Motor OilFull Synthetic5W-40Faster PenetrationCheck on Amazon
Mobil 1 Synthetic Motor OilFull Synthetic0W-40Increased MileageCheck on Amazon
Mobil Super Delvac Motor OilConventional15W-40Cold Cranking

Check on Amazon

Royal Purple Motor OilFull Synthetic15W-40Catalytic EmissionCheck on Amazon
Amsoil Signature Synthetic Motor OilFull Synthetic5W-30Improved EfficiencyCheck on Amazon

Top 6 Best Engine Oil for Duramax Engine

The quick comparison table above should give some insight. Let’s check out our in-depth Duramax oil reviews one by one.

1 – Shell Rotella T6 Full Synthetic Heavy Duty Engine Oil – 5W-40

Shell Rotella features a revolutionary Triple Protection Plus technology that enhances the engine’s output and protection. Like other Shell lubricants, Rotella injects new life into the Duramax diesel engines with optimal performance.

Its 5W-40 consistency will keep you moving irrespective of the weather conditions, and it ameliorates the engine’s cleanliness without needing to be replaced very often.

Features and Benefits

Perfect Compatibility

It ensures and maintains system compliance by using a low-ash formula in manufacturing. It keeps the engine firing optimally on all cylinders and offers premium fuel economy.

Enhanced Engine Functioning

It is fully synthetic oil, which means it offers the ideal burning of fuel inside the engine. In addition to its Triple Protection Plus technology, it uses premium additives which reduce engine wear, and deposits of any kind.

Solid Protection against Adverse Temperatures

It maintains optimal pressure and viscosity, thanks to high shear stability. It offers near-perfect cold starts and dependable output in summers, maintaining the optimal engine temperature.


·         Enhances engine performance and durability

·         Incorporates premium additives

·         One of the most premium formulations in the fully synthetic oil range

·         Maintains the standard temperature and pressure


·         Packaging needs to be improved to avoid contamination

2 – Liqui Moly 2041 Premium Synthetic Motor Oil – 5W-40

Liqui Moly is one of the most respected names in the lubricants and motor oil industry, and thanks to its cutting-edge technologies, the products it offers are top-notch.

Liqui Moly 2041 Premium synthetic oil is one of the best options for your Duramax engine and ensures optimal performance and output. It optimally lubricates all the parts of the engine and with a 5W-40 viscosity rating, it would work perfectly in all weather conditions.

Features and Benefits

Flawless Engine Cleansing

This premium oil has special additives that offer flawless cleaning and lubrication of the engine’s interior. It gets rid of all the harmful deposits, sludge, and other debris, acting as a flush system as well. Its cleansing property makes it so desirable and popular among Duramax enthusiasts.

Optimal Fuel Efficiency

The engine works perfectly when the temperature is maintained, friction is reduced due to lubrication, and no deposits are poisoning the performance. Liqui Moly oil achieves all this and ensures optimal fuel economy.

Incredible Formula and Consistency

It is a fully synthetic motor oil with the highest quality additives. This offers premium performance, longevity of the engine parts, and longer oil change intervals. Perfect for cold starts and suitable for hot summers, Liqui Moly 2041 is a perfect oil for Duramax engine.


·         Ideal for both diesel and gasoline engines

·         High-quality additives and other constituents

·         Offers longer oil change intervals

·         Suitable for all weathers


·         Can be costly upfront

·         Could spill while pouring if not too careful and precise

3 – Mobil 1 Synthetic Motor Oil – 0W-40

Mobil1 needs no introduction, it has been offering top-quality lubricants for ages now. Their synthetic motor oil is one such great example and a great option among the best oil for Duramax engines.

It offers reliable engine protection with its superb lubrication, a wide range of temperature coverage, and a unique 0W-40 rating for all your diesel engine requirements.

Features and Benefits

Better Mileage

It prevents unnecessary burning of oil and reduces wear and damage to the engine’s components. Though not considerable, it offers improved mileage and economy.

Enhanced Mechanical Durability

A fully synthetic formulation protects the moving parts of the engine and the seals from getting damaged, offering better durability and ensuring the longevity of Duramax engine.

Ideal Temperature Tolerance

In terms of performance in different temperatures, Mobil 1 oil can be regarded as one of the best oils, especially for LBZ type of Duramax engines, due to its unique 0W-40 SAE rating.


·         Covers a wider temperature range

·         Gets rid of all the internal debris and deposits

·         Optimal lubrication and wear reduction

·         A perfect choice for high-mileage Duramax engines


·         Costs higher than better-formulated competitors, with negligible fuel economy.

4 – Mobil Super Delvac 1300 Motor Oil – 15W-40

It is designed specifically for commercial and heavy-duty requirements and serves the purpose amicably. Semi-synthetic composition with a 15W-40 rating means no on-road or off-road job is tough for your Duramax engine.

It is also great for long-term durability and dependable performance in cold environments.

Features and Benefits

Ideal for Winters

It ensures cold cranking efficiency and optimal performance in cold temperatures. The unique 15W-40 viscosity is perfect for your Duramax truck.

Performance Versatility

It is compatible with a range of Duramax engines and has rugged properties to keep you moving in tough conditions and terrains.

Suitable for Commercial Use

Due to its semi-synthetic nature, it is ideal for commercial usage and a suitable option to ensure the durability of commercial engines.


·         Great for commercial usage

·         Compatible with modern engine technology

·         Dependable improvement in fuel economy


·         Not as premium as a fully synthetic oil

·         Needs replacement more often

·         Oil gets too dark if burnt and after extended mileage

5 – Royal Purple Motor Oil – 15W-40

Its high-quality additives offer superior engine performance, and thanks to its fully synthetic formula, Royal Purple 04154 offers matchless protection to the engine parts.

15W-40 viscosity rating promises excellent fuel efficiency and optimal output at different temperatures. And it doesn’t even require any special treatment or upgrades for all its properties.

Features and Benefits

Wider Compatibility Range

It is remarkably compatible with ethanol-containing fuels and both old and newer model engines work exceptionally well with its 15W-40 grade. Moreover, this is the finest oil for a Duramax LML type and can be used with other conventional or synthetic oils as well. 

Premium Constituents and Additives

Its premium additives ensure that the wear and friction in the engine are kept at a minimum, with its ZDDP technology offering unparalleled durability. It gets rid of all the debris, remnants, and particularly the white sludge in your Duramax engine.

Enhanced Performance

With its superior formulation, viscosity, and unique consistency, performance is bound to take a leap. You’d get additional wear protection with enhanced output.


·         Optimally cleans the emission catalyst system

·         Better engine cleaning and performance

·         Compatible with a range of oils and fuels

·         Offers great temperature coverage


·         Packaging is deceptive and needs improvement

6 – Amsoil Signature Series Synthetic Motor oil – 5W-30

The best oil for Duramax Engine list would be incomplete without the mention of Amsoil Signature. This fully synthetic oil offers superior protection with its assertive acid neutralizing properties and optimal lubrication.

Its premium formulation and high TBN offer optimal fuel efficiency, prevent low viscosity breakdown and enhance performance in any kind of weather conditions.

Features and Benefits

Offers Unparalleled Performance

The secret behind its ultimate performance enhancement is the considerable reduction in viscosity breakdown. It offers nearly 40% better acid neutralization than its competitors due to a better TBN (total base number).

Dependable Fuel Efficiency

Due to better lubrication and temperature maintenance, it offers a considerably fair fuel economy. You also get generous 10,000-mile oil change intervals with Amsoil Signature Series, one of the best oils for Duramax engine.

Improved Cleaning Properties

It also offers enhanced cleaning of the inside of the Duramax engine, thanks to the penetration qualities of premium additives used in its formulation. It clears out all the sludge and deposits, with the neutralization of harmful acids in the meanwhile.


·         Optimal engine startup and idling

·         Brilliant wear protection and lubrication

·         Enhancement in fuel efficiency and performance

·         High-quality additives and other ingredients


·         Could offer even better fuel economy, like the competitors.

How to Choose the Right Oil for Duramax Diesel Engines?

To make sure that your Duramax engine gives optimal output and performance, you ought to feed it the best engine oil available.

Although you should consult your owner’s manual for the exact guidelines, keep these key factors in mind if you’re wondering how to choose the right oil for Duramax diesel engines.

Oil Grade

The first thing you have to keep in mind is the grade of the engine oil. It defines the consistency and viscosity of the oil, and how it behaves in the extremes of temperature.

Although the majority of the engines use 5W-30 grade oil, you should check the owner’s manual or consult your dealership before shopping for your Duramax.

Oil Type

The next consideration should be the type or quality of the oil. There are 3 types of engine oils available, fully synthetic, semi-synthetic, and conventional oils.

Fully synthetic are the highest quality oils that use premium additives and offer the best performance and wear protection. Semi-synthetics are formed by amalgamating the fully synthetic and conventional oils and fall in-between.

Conventional oils are the lowest in quality and least desirable but are often used in commercial vehicles.

Formulation and Additives

Any premium oil composition must possess quality additives and additional constituents. Certain advantageous properties are offered by these substances.

It makes the engine resistant to wear, rust, accumulation of sludge, and corrosion. optimal lubrication and reduced friction ensure longevity and better performance.


Q1- What is the most suitable engine oil for Duramax Diesel?

Despite the tough competition, the Liqui Moly 2041 premium synthetic motor oil turns out to be the best oil for Duramax engine. Thanks to its superior quality, long-term serviceability, and optimal performance.

Q2- How often should you change the oil in your Duramax engine?

The recommended oil change interval for the Duramax engines is between 5,000-7,500 miles or 8-12 months, whichever comes first.

Q3- What is the oil capacity of Duramax diesel engine?

Most of the Duramax diesel engines have an oil capacity of 9-10 liters.

Final Thoughts

To keep the Duramax engines functioning well over time, using high-quality oil is necessary. An effective engine performance enhancement can be ensured by a premium formula. The best oil for Duramax diesel engines might also produce results that are adequate, and ensure long-term durability with better fuel economy.

If you’re looking to buy engine oil for your vehicle, Liqui Moly Premium synthetic oil should be your top pick as it offers unrivaled performance, wear protection, all-weather coverage, and superb fuel economy. It can be considered the best oil for Duramax engines and has a history behind it to prove the fact.