Keeping your diesel truck in top condition means staying on top of routine maintenance. One of the most important tasks is changing the oil.
Unlike gas engines, diesel engines run hotter, carry heavier loads, and generate more soot. That means they need clean oil more often to keep running strong.
If youโre new to diesel trucks or just want to learn how to take better care of yours, this guide is for you.
We’ll walk you through how to change the oil properlyโstep-by-stepโwith simple instructions anyone can follow, even if youโve never touched a wrench before.
Why Oil Changes Matter for Diesel Trucks
Your truckโs engine is made up of many moving parts, and oil helps those parts move smoothly. It reduces friction, carries away heat, and traps dirt, metal shavings, and other nasty stuff that builds up over time.
If your oil gets too old or dirty, it canโt do its job. The engine will start to wear down faster, run hotter, and work harder. Over time, this can cause serious damage and cost you thousands in repairs.
In diesel engines, this is even more important. Diesel trucks are built for tough jobsโpulling trailers, hauling loads, or working long hours. Because of that, their oil needs to be clean and fresh more often than in a regular gas car.
Changing your oil on time keeps your truck running smooth, protects the engine, and helps it last longer.
How Often Should You Change Diesel Oil?
The right oil change schedule depends on how and where you drive. Hereโs a basic guide:
- Every 5,000 to 7,500 miles for most diesel trucks
- Every 3,000 to 5,000 miles if you:
- Tow heavy loads
- Drive in extreme heat or cold
- Sit in traffic often
- Go off-road or drive on dusty roads
Some newer diesel trucks have oil life monitors that tell you when itโs time to change the oil. But even then, itโs smart to check the oil yourself once in a while.
Also, always check your ownerโs manual. It tells you exactly when to change the oil and what type of oil and filter your truck needs.
What Youโll Need
Before you start, gather everything so you donโt have to run to the store halfway through the job. Hereโs a simple checklist:
Tools:
- Socket wrench and oil filter wrench
- Jack and jack stands (if your truck sits low)
- Funnel
- Oil drain pan
- Gloves and rags or paper towels
Supplies:
- New diesel engine oil (make sure itโs the right grade and type)
- New oil filter (designed for your truckโs engine)
- Oil container for recycling used oil
Tip: Many auto parts stores sell oil change kits for diesel trucks that include everything you need.
Step-by-Step: How to Change Oil in a Diesel Truck
Step 1: Warm Up the Engine
Let the truck run for 5 to 10 minutes. Warm oil flows out easier and helps remove more gunk from inside the engine. Donโt let it get too hotโyou want it warm, not scorching.
Step 2: Park Safely and Set Up
- Park the truck on a flat, level surface.
- Turn off the engine and let it sit for a few minutes.
- If needed, jack up the truck and use jack stands for safety. Never rely on just the jack.
- Put on your gloves, open the hood, and get ready.
Step 3: Drain the Old Oil
- Place the drain pan under the oil drain plug.
- Use your socket wrench to unscrew the plug (usually on the bottom of the oil pan).
- Be carefulโhot oil may come out fast. Let it drain completely. This may take 5โ10 minutes.
- Once all the oil is out, clean the plug and screw it back in snugly (but donโt overtighten).
Step 4: Remove the Old Oil Filter
- Use an oil filter wrench to twist off the old filter.
- Oil will likely spill out, so keep your pan or rag nearby.
- Double-check that the rubber gasket (the black ring) came off with the filter. If itโs still stuck to the engine, peel it off.
Step 5: Install the New Oil Filter
- Lightly coat the rubber gasket on the new filter with fresh oil. This helps it seal tightly.
- Screw on the new filter by hand. Once it touches the base, give it about three-quarters of a turn more. Thatโs itโno tools needed.
Step 6: Add New Oil
- Open the oil cap on top of the engine.
- Insert the funnel and slowly pour in the new oil.
- Check your manual to see how much oil you needโusually between 10 to 15 quarts for a diesel engine.
- After adding all the oil, close the cap.
Step 7: Check the Oil Level
- Start the engine and let it run for 1โ2 minutes.
- Turn it off and wait another minute.
- Pull out the dipstick, wipe it clean, reinsert it, then pull it out again to check the level.
- If itโs low, add a little more oil. If itโs just right, youโre good to go.
Step 8: Clean Up and Recycle the Oil
- Carefully pour the old oil into a sealed container.
- Do not dump it on the ground or in the trash. Take it to a local auto shop, parts store, or recycling center that accepts used oil.
- Throw away the old filter or recycle it, too.
Tips for a Clean and Easy Oil Change
- Wear old clothes or a shop apronโoil stains are tough to remove.
- Use a large drain pan to avoid spills.
- Donโt skip the oil filterโchanging just the oil is only half the job.
- Mark your mileage and date after every oil change so youโll know when itโs time again.
- Label containers for used oil to avoid confusion.
- Tighten by handโtoo much force can strip threads or damage parts.
Final Thoughts
Changing the oil in your diesel truck is one of the best ways to protect your engine and save money. You donโt need to be an expert mechanic. Just follow the steps, use the right tools, and take your time.
By learning to do it yourself, youโll feel more confident about maintaining your truckโand youโll keep it running stronger for longer.
So next time your diesel truck is due for an oil change, donโt stress. Get your tools, grab the right oil, and knock it out like a pro. Your truck (and your wallet) will thank you.



