Maintaining a peak-performing diesel engine is an essential part of owning a diesel vehicle. The best way to keep the gears running is by using only the best synthetic oil for diesel engines. But how do you know which synthetic oil is best for your diesel engine?
To help you with that, we’ve listed the best brands and compared them. We’ve also picked out some of their most amazing products. Our judgment is based on grading, certification, ODI, and engine compatibility.
So without any further ado, let’s get started!
Click here to skip to our recommended pick!
- Extends the life of the engine.
- Reduces sludge and deposits.
- Long life of seals and gaskets.
- Reduces friction.
- Conserves engine power.
- Prevents abrasion and corrosion.
- Works in extreme conditions.
- Protects the engine from oxidation.
- Enhances fuel efficiency.
- Protects from corrosion.
- Superior wear protection.
- Extends oil change intervals.
- Promotes longer engine life.
- More efficient engine function.
- Reduces emissions from the exhaust.
- Requires lesser frequent draining.
- Prevents wear six times faster.
- Better fuel economy.
Overall #1 Rated Pick
Mobil 1 Super 96819 15W-40 Delvac
We chose the Mobil 1 Delvac Super 1300 as our top pick. The reason for this is that it compares so well to the other products in the market. It features an extended oil drain interval that goes 1.5 times beyond the regular OEM recommendation. Plus, it’s known to exceed most, if not all, API requirements. This includes API CK-4, CI-4 PLUS, CH-4, and many more.
The Super 1300 is always ready to go over the top. It’s the perfect choice for heavy-duty engines such as threshers, harvesters, tractors, trucks, and ships. It’s also one of the best when it comes to driving both on and off the highway. If you’re someone who owns a truck or some sort of heavy vehicle, then this is the best diesel oil for you. If you own a fleet of excavators, cranes, and construction vehicles, then the Super 1300 is also the best deal for you.
The top best product [hide]
Synthetic Diesel Oil Comparison
Want to know what the best synthetic oils are for diesel trucks and wagons? The best way to do so is to look into what others have to say. A quick review of the marketplace reveals that most suggest big brands such as Mobil 1 and Castrol. But many times, it’s not about the brand, but actually the mileage of your car.
If your car has lower mileage, a lighter-grade full synthetic oil for diesel engines will work. It includes anything from 5W-20 to 5W-30. Lighter oils require less frequent oil changes, and are great at keeping your engine in top shape.
If your car has higher mileage, you’ll need heavier grade oil. For example, on a Honda Accord, 5W-30 synthetic diesel oil does the trick. You can also opt for the 5W-40 synthetic diesel oil if your vehicle is a bit older. Both of these will help to preserve the engine’s life and keep the car running smoothly. 10W-30 oil seems to work great too.
However, many people are of the view that you should just stick to the manual. Frequently, the car/truck has a brand of oil that it’s best compatible with it.
| Brand | SAE | Summary |
| Mobil 1 | 15W-40 | Best for extreme conditions |
| Castrol | 5W-30 | Best prevents oil breakdown |
| Shell Rotella | 15W-40 | Best for high compatibility |
| Valvoline | 5W-30 | Best for product and grade versatility |
Best Synthetic Oil for Diesel Engines
Mobil 1 Super 96819 15W-40 Delvac
- Meets API CK-4 specifications.
- Soot and viscosity control.
- Excellent TBN reserves.
- Fluid even at low temperatures.
- Compatible with most car parts.
Castrol EDGE 5W-30 C3 Advanced Full Synthetic Motor Oil
- Strengthens oil film by 30%.
- Fights wear six times better.
- Meets OEM specifications.
- Uses Fluid Titanium.
- Minimal friction for better performance.
Valvoline Premium Blue Extreme SAE 5W-40 Full Synthetic Engine Oil
- Safer starts in freezing weather.
- Meets many requirements.
- Better fuel economy.
- Protects against oil oxidation.
- For both on and off-road.
Royal Purple 15W 40
- Goes beyond Dexos1 specs.
- Patented ZDDP additives.
- Removes existing sludge and deposits.
- API-licensed diesel oil.
- Increases efficiency of fuel consumption.
Shell Rotella T4 15W 40
- 50% longer oxidation protection.
- API-CK-4 licensed.
- Prevents 50% more wear.
- More durable emission control system.
- Better oil aeration.
Castrol EDGE 03087 5W-30
- 20,000 miles drain interval.
- Best for towing and hauling.
- Fluid Titanium technology.
- Reduced engine deposits.
- Works in extreme temperatures.
Synthetic Oil for Diesel Engines Brands
Here are the top brands for the best synthetic diesel engine oils:
Castrol Synthetic Diesel Oil
Castrol is one of the world’s top leading brands that manufactures and sells lubricants. Based in the UK, this 120-year-old company operates in over 40 different countries. It produces lubricants solely made for motorbikes, two and four-stroke engines, and diesel engines. All of their products, especially the gas and diesel oils, keep your engine in top shape. They prevent knocking, burning, depositing, and control exhaust fumes.
If you’re looking into buying Castrol diesel oil, we recommend the Castrol EDGE Extended Performance. This oil is made for use in tractors, tow trucks, and heavy agricultural equipment. It’s excellent for home use as well, if you own a semi-truck or a wagon.
Valvoline Synthetic Diesel Oil
Valvoline Inc. is a worldwide manufacturer, supplier, and marketer of premium quality lubricants and oils. Having a rich history of over 150 years, the brand has been ranked as the No. Three motor oil brands for passenger cars. And their diesel engine oils are no different.
The brand also prides itself on providing quick car services, operating over 14,000 such centers. The Valvoline trademark brand name is an industry-standard diesel engine oil manufacturer.
One of their best assets is the Premium Blue Extreme oil for diesel engines. Available in multiple grading, the oil is essential for your truck or trailer. Due to its cheap cost, it’s also preferred for larger fleets and dispatchers, especially online stores.
Royal Purple Synthetic Diesel Oil
Another name that shines out from the rest is Royal Purple. Situated in Porter, Texas, Royal Purple provides the widest range of products for cars and trucks. This company has had over two centuries of experience, making formulae for engine lubricants. While other companies strive to compete in the synthetic world, Royal Purple trumps even the natural variants.
For anyone who wants to try it, we’d recommend the Royal Purple Duralec Super. It’s one of the best diesel engine oils if you want to maximize your engine’s performance. It works in all conditions- wet, dry, cold, humid, and at extreme temperatures.
Mobil 1 Synthetic Diesel Oil
Last but not least, we have the Mobil 1 synthetic diesel oil. This is, by far, the most commonly heard-of brand. But the performance isn’t just hearsay– Mobil 1 certainly outperforms some of the biggest contenders. With over 46 years of experience, Mobil 1 stands at the top of the oil industry.
This brand produces lubricants for cars, trucks, motorbikes, tractors, and even heavy machinery. Their product range is versatile and extant. Each series of diesel oils is designed with your engine’s performance in mind.
If you want to try it out, then why not try your luck with the Mobil 1 Delvac Super 1300? It’s a good product, given the low price range. It’s best to prevent knocking, burning, and controlling exhaust fumes. And it works even in the winters, providing a lightning-fast ignition.
Synthetic Oil for Diesel Engines – Buyer’s Guide
Knowing what should go into your delicate diesel engine is no less than an art. You need to do a lot of research, search through forums, and refer to various websites. To save you from all that hassle, here are a few tips that will help you make the right decision.
Oil viscosity
Oil viscosity is a measure of how easily you can pour the oil at a specific temperature. It’s usually represented in the format XW-XX. The ‘W’ stands for winter, and the X before that the viscosity of the oil at 0 degrees Celsius. The next two X’s represent the viscosity at 100 degrees Celsius. All of this will tell you thick or thin the oil becomes in certain weather.
As a general rule, the higher the W rating, the less compatible oil is in the winters. Also, if the high-temperature viscosity is higher, that means the oil will thin less.
For instance, 0W-30 grade oil will thicken less in the cold and thin faster in the heat. A 15W-50 grade oil, however, won’t work well in either weather. This highly depends on the engine and car model you have, so always be sure to do research on that.
Oil Drain Interval
This refers to how often you need to change the motor oil while driving. It’s usually measured in the number of miles you should run before changing it. Many owners believe you should change the oil every 5,000 miles. But the interval is given on most diesel engine oil boxes.
A longer interval will save you the pain of changing the oil every so often, which is especially annoying if you’re always making short trips, or own an extensive fleet of heavy vehicles.
Changing Oil
Changing the oil in your diesel engine is pretty simple if done right. You’ll be needing the oil, oil filter, drain pan, a wrench, a funnel, some gloves, and an empty container. Drain your water separator, turn off the engine, and remove the dipstick.
Raise and secure your vehicle and remove the drain bolt. Let it drain completely, replace the bolt, and then remove the oil filter. Replace with the new filter.
Now open the fill cap and use the funnel to pour in the new oil. Start your own and reset the oil lamp and wait for a few minutes. Now your vehicle is ready to run!
If all that is too wordy, then you can always have a look at this video below:
