From unique fuel to specialized additives, diesel engines require special care. Whenever you’re shopping for diesel engine oil, the first thing you should consider is the manufacturer’s recommendations. However, some engines have a range of recommended oil viscosity grades. To help you make the right choice, here are four factors to consider when choosing oil for your diesel vehicle.
Want to Consult a Mechanic? See what experts have to say about choosing the right oil
Engine enhancements
If you’ve beefed up your engine with performance-boosting add-ons, your vehicle’s diesel engine operates with a higher amount of cylinder pressure than the manufacturer intended. As a result, a thin oil probably won’t provide the protection it needs. Instead, reach for a thicker formulation, like 15W-40.
Climate
Extreme temperatures can have a major impact on the performance and longevity of your truck’s diesel engine. Excess heat can put stress on the engine’s components, and if its oil isn’t viscous enough, it won’t lubricate properly. So if you’re in a hot climate, consider reaching for an oil with a higher viscosity grade. On the other hand, chilly weather can make oil freeze so thick, it’s practically a gel. Cold starting your engine under these conditions can leave it improperly lubricated — ultimately leading to engine damage. Prevent this by picking an oil with a lower winter viscosity, indicated by the number followed by a W in its viscosity grade.
Engine age
Older engines need the protection that a thicker oil formulation provides. If this is your situation, consider filling your vehicle’s engine with 15W-40 grade oil. This may slightly diminish your fuel economy, however. If you’d like a balance between fuel economy and protection, consider grabbing a 10W-30 bottle of oil.
Fuel economy
If you’re looking to maximize fuel economy, Fleet Owner suggests picking a fully synthetic oil for a boost of 2-3 percent more miles per gallon. Reach for 5W-40 or 10W-30 oil to keep things operating smoothly.
Want more tips? Check out our guide to preparing your diesel truck for winter.
Kimiko Kidd is a native Daytonian. She graduated from Wright State University with degrees in environmental science and sociology. She loves her trusty old Honda Civic, but dreams of owning a 1974 Ford Falcon XB with a custom paint job and a vintage Kawasaki Z1000. In her free time, Kimiko can be found watercolor-painting, baking muffins, collecting rocks, playing old-school Nintendo games, writing her novel, sewing stuffed animals, and cosplaying as her favorite Mad Max characters. See more articles by Kimiko.
