Vehicle ownership is an important part of life. Once you’ve made the decision to purchase a vehicle, you want to protect your investment. Diesel trucks work extra hard and are often a core component of your work, livelihood, and lifestyle choices. Whether your diesel truck is for work or recreation, you want to make sure to properly maintain your machine to extend its life and protect your investment. Taking the extra step to protect your truck and its mechanical components can be enough to keep your vehicle working for years to come.
We’ve compiled a list of suggested diesel truck maintenance items to help keep your machine in tip-top shape. In making our list, we conducted research and considered expert opinions. Here’s our list of diesel truck maintenance tips that are the most effective and cost-efficient.
Change the Oil
You’ll want to perform regular oil changes on your diesel truck, just like on a gasoline engine. Neglecting regular oil changes for a diesel truck can be disastrous. Old and dirty oil can cause clogs in a diesel-powered engine, causing damage due to unnecessary friction and heat. The vehicle’s owner’s manual will give you specific guidelines for your make and model, but most diesel trucks require regular oil changes every 3,000 to 5,000 miles.
Replace the Fuel Filters
Most diesel engines have two fuel filters. The primary fuel filter runs between the gas tank and the engine while the secondary is between the transfer pump and fuel injectors. Because diesel is less refined than regular gas, the fuel often absorbs more water from condensation in the tank. Water particles in diesel could cause:
- Decrease in horsepower
- Engine stalls
- Fuel injector explosions
Most diesel trucks benefit from fuel filter changes every 10,000 to 15,000 miles. The frequency at which you will need to change your fuel filters will vary depending on your overall vehicle usage, environmental conditions, and the quality of the fuel you use. Most manufacturers recommend replacing both the primary and secondary filters at the same time to maximize efficiency.
Check the Air Filter
A quality air filter is an important part of any vehicle. For diesel trucks, dirty air filters can obstruct the engine, forcing it to burn more fuel to perform well. Most owners’ manuals suggest replacing the air filter about every 12,000 miles. However, if you notice a decrease in engine performance, weak acceleration, or an increase in engine wear, a dingy air filter may be the problem. Keeping a clean air filter plays an important role in proper diesel truck maintenance.
Care for the Radiator and Coolant
A vehicle’s radiator is part of your vehicle’s cooling system that helps to keep the engine running smoothing by taking heat from the engine and moving it into the air. The coolant travels to the engine, absorbs the heat, and cycles back to the radiator, which dissipates the heat into the air. The coolant then travels back to the engine and repeats the cycle.
Because diesel engines operate at high temperatures, the coolant is an important part of engine maintenance. Be sure to use an OEM-recommended coolant for best results. The coolant should be clean and maintained at the manual’s recommended levels. Coolant that is too acidic can wear down the radiator and cause corrosion. These smaller issues can quickly lead to engine damage and result in costly repairs.
Diesel engines run hotter than gas motors, so their components are more susceptible to overheating. Overheating can warp important parts such as cylinder and gasket seals. Small damages to engine components can lead to eventual engine failure. Vehicle manufacturer suggestions vary in their recommendation for periodic radiator fluid changes, but most fall somewhere between 40,000 to 60,000 miles. If you notice an orange or green-tinged fluid leaking under your truck, a sweet maple-syrup-like scent emanating from your vehicle, or steam coming from under the hood, get your system evaluated.
Plan for Repairs
A vehicle owner must prepare for the inevitable repairs, especially if you keep your vehicle for several years. Invest in parts early and try to get the best parts available. Buy parts with a lifetime warranty, especially if you plan on keeping your vehicle for a long time or passing it down to a child or other family member.
Depending on the manufacturer, some unexpected parts, such as brake pads, starters, alternators, and oil seals, come with lifetime warranties. Although the initial cost may be a bit more, it is an investment that will pay off over the life of the vehicle.
Consider a Fuel Stabilizer
If you will be storing your diesel truck for a while, or if it is not a daily work truck, you might want to invest in a quality fuel stabilizer. Diesel vehicles can have problems when they are low on fuel or when the fuel filter is clogged. A fuel stabilizer is an additive you can pour into your vehicle when you have a full gas tank to help improve the quality of the fuel, especially over long periods of storage.
Understanding the responsibilities of diesel truck maintenance can help you save thousands in potential repairs in the future and prolong the life of your vehicle. Ultimately, your maintenance priorities should keep your individual needs, budget, and the manufacturer’s recommendations in mind.

At FIXD, our mission is to make car ownership as simple, easy, and affordable as possible. Our research team utilizes the latest automotive data and insights to create tools and resources that help drivers get peace of mind and save money over the life of their car.