6 Tips For Heavy-Duty Truck Oil & Fluid Maintenance

Heavy-duty oil is the lifeblood of your truck—it lubricates all of the engine components that are constantly under the stress of friction. Without proper oil maintenance, your truck's engine will eventually experience decreased efficiency due to the metal-on-metal contact of each component, leading to expensive repairs, frequent downtime, and even complete engine failure if you’re not careful. 

Although it may seem repetitive and bothersome, oil and fluid maintenance is what will help prevent your engine from getting to this point. Simple tasks like checking your oil, filters, belts, and hoses, following recommended service intervals, inspecting and replacing fluids, and cleaning and inspecting your coolant system, will keep your engine from suffering an impromptu death.

In this article, we’ll be exploring six methods you can employ in your operation to reap more performance from your engine and prevent it from wearing down.

Check Oil and Oil Filters Regularly

The first step in an effective oil and fluid maintenance regime is checking the oil and filters for oil levels and signs of contamination. Although you could take your truck to a service center for oil and filter maintenance, this step is something every owner-operator and fleet owner should know how to do to save money in the long run.

When checking the oil level of your heavy-duty truck, follow these steps:

1. Park the truck on level ground and wait a few minutes for the oil to settle after shutting off the engine.
2. Locate the oil dipstick, which is usually located near the top of the engine and is labelled with the word "oil" or a picture of an oil can.
3. Remove the dipstick and wipe it clean with a rag or paper towel.
4. Reinsert the dipstick all the way into the tube and then remove it again.
5. Check the oil level on the dipstick. The oil level should be between the "full" and "low" marks on the dipstick. If the oil level is low, add oil as necessary.
6. Check the oil level on the dipstick while the engine is running.
7. Check the oil level when the engine is cold as well, as the oil level will be more accurate when the engine is cold.
8. Check the oil’ color and viscosity. If it’s dark and dirty, your oil is contaminated and due for an oil change.

‍

You should be doing this pretty frequently—once a week, to be precise. If the oil level is low, add more oil as per the manufacturer's specifications. In addition, we recommend inspecting and changing your oil filter every time you go through this step, as it needs TLC just as much as your oil. 

Your oil filter is at the forefront of protecting your engine since it’s in charge of filtering debris and particulate matter. When it reaches maximum capacity, all dirt and particulate matter will be free to enter the vehicle, speeding up the wear and tear process.

Follow Recommended Service Intervals

Every manufacturer, make, and model has a different playbook to follow. We advise you to check your truck’s owner’s manual for specific guidelines on recommended service intervals before you get your business rolling. 

If you don’t have your owner’s manual handy, we suggest you get your oil and fuel filter changed every 5,000 to 20,000 miles, depending on the type of work you do with your truck and your driving habits. For transmission fluid, power steering fluid, coolant, and brake fluid, it is suggested you take your truck to a repair shop and get it inspected by a professional every 30,000 to 60,000 miles.

Inspect and Replace Air Intake Filters

As part of any effective preventive maintenance program, inspecting and replacing your air intake filter can help prolong the life of your engine by allowing clean air to flow into the engine chamber to aid in the combustion process. Similar to oil filter service intervals, air intake filters need to be checked and replaced regularly, typically every 15,000 to 30,000 miles. If you’re too busy with deliveries or you simply can’t find the time to replace your air intake filter, you could experience poor engine performance, reduced fuel economy, and strange noises coming from the engine bay. 

Inspect and Replace Fluids

Fluids such as transmission fluid, power steering fluid, and brake fluid need to be inspected and replaced often, just like your engine’s oil and filters. Over time, fluids tend to break down and lose their ability to lubricate and protect the components they come into contact with.

We advise you to schedule a service appointment every 30,000 to 60,000 miles, or 2 to 3 years, to flush out your old lubricants and replace them with high-quality fluids at the hands of a professional. By sticking to this regime, you’ll be saving big on unexpected repairs and replacements.

Clean and Inspect Coolant System

While the oil in your engine helps keep everything lubricated, coolant absorbs the heat produced by your engine and keeps combustion temperatures regulated. The coolant system consists of an interconnected web of components, including the radiator, hoses, water pump, and thermostat. Over time, your coolant and other components can become contaminated, leading to decreased performance and eventually, engine damage.

Choose the Right High-Quality Oil

Choosing the right high-quality engine oil for your heavy-duty truck should be a priority in your oil and fluid maintenance program—it’ll help achieve optimal engine performance, fuel economy, and reduced maintenance costs. 

To start, we recommend you follow the advice of your truck’s OEM manual for guidance on oil selection, as the manufacturer generally knows best. That being said, if you operate your truck in poor weather conditions or extreme temperatures, you might want to invest in a lower or higher viscosity grade or SAE grade. In a warmer climate, stick to high-viscosity oil as it will resist breaking down due to higher external temperatures. On the other end and in colder weather, opt for low-viscosity oil, as it will help with the flow of oil in lower ambient temperatures. 

Another choice you’ll have to make is between mineral, synthetic, and a mix of both. We suggest you go with fully synthetic oil or a blend, as synthetic oil tends to perform better in varied weather conditions while coating your engine with an additional layer of protection.

Final Words

By regularly checking oil and oil filters regularly, following recommended service intervals, inspecting and replacing air intake filters, cleaning and inspecting your coolant system, and using high-quality oil suited to your operation, you’ll be able to stay ahead of the competition. With proper oil and fluid maintenance, your diesel rig can continue to serve your business for years to come.

‍