Simplify Your Diesel Truck Care: A Step-by-Step Guide with Doc’s Diesel

How Doc’s Diesel is Making Your Maintenance Day a Breeze

Photos by Ryan Sinkler

As a diesel truck owner, routine maintenance is equal parts rewarding and frustrating. While the actual act of changing your engine oil and filter is a pretty straightforward process, it’s all the steps leading up to that moment that can be a bit of a headache.

There’s nothing worse than calling your local parts store, talking to the kid behind the counter, and repetitively getting asked what trim your truck is, like it’s going to make the life or death difference for your engine oil and filter. What’s worse is getting to the store and finding that they’re out of your oil, don’t stock your filter, or finding out that your local dealership wants an exorbitant amount of money for your filters. All of that is why the folks at Doc’s Diesel are changing the way you do your diesel maintenance.

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Founded in 2020 in a small Ohio town, the team at Doc’s Diesel has one goal: to make diesel maintenance easy. For the last four years the Doc’s team has been providing high-quality oil and filters for your diesel truck, and they make finding the right filters for your truck a breeze.

Let’s get started!

**Step 1:** Like any good oil change, we’re going to start with—you guessed it—removing the old engine oil. Grab yourself a ratchet and socket that fits your drain plug and give it a good twist. As always, nitrile gloves are a good idea here, though we didn’t have any on hand at the time. They’re not a requirement, but they just make cleanup a lot easier. Also, make sure that you have your drain pan ready or else you’ll end up with oil all over the floor. Nobody likes that.

**Step 2:** As the drain plug comes out, I always like to take a peek at it for any metal shavings. While not an end-all-be-all sign of engine wear, a magnetic drain plug is nice for giving you peace of mind that your truck is running the way it should be.

**Step 3:** Now that we have the old oil drained, it’s time to pull off the old oil filter. The filter location is going to change on every truck. For some absurd reason, however, General Motors decided on this LBZ to place it directly above the front driveshaft U-joint and the best part, it’s horizontal. I’d like to tell you that I have some secret to doing this without making a mess, but to be honest, it’s just one of those things you kind of get used to after awhile. Oh well, the show must go on.

**Step 4:** Out with the old, in with the new! Once that old filter is out, verify that your old filter O-ring came with it. It’s not uncommon to see these O-rings stick to the oil filter housing and when you screw the new filter in place, this double O-ring can cause a leak. Start by lubing the O-ring on the new filter with a little oil to ensure a proper seal, and then spin it into place. Some will tell you to pre-fill these filters before they go on the truck, but Duramax guys will attest that this really isn’t possible given the horizontal orientation of the filter. Spin it tight with your hand, and then give it a good quarter to half turn snug with a filter wrench. Now is a good time to triple check that you reinstalled the drain plug as well—you don’t want to leak all that nice new oil on the shop floor.

**Step 5:** Now that your new filter is on, it’s time to refill your engine oil. Today we’re using Doc’s “The 15W-40 Full Synthetic” oil. What makes this oil great is that the folks at Doc’s actually partnered with another killer name in the industry, Hot Shot’s Secret. This oil is specifically formulated with an additive package for your diesel truck and is made specifically for diesel engines. It is manufactured to CK-4 specifications and features a patented FR3 Nano Technology, which provides protection, longevity, and performance gains that other synthetics won’t allow. The truck takes about 10 quarts, so we’ll get it all filled up and ready to go.

**Step 6:** Now that we’ve got it filled, we’re going to fire up the truck, and then check the engine oil level with the dipstick and top it off if we need to. Once it’s full, you’re good to go!

ABOUT DOC’S DIESEL

Doc’s Diesel, founded in 2020, revolutionizes diesel maintenance with its premium aftermarket filters that meet or exceed OEM standards. Inspired by the entrepreneurial spirit of “Grandpa Doc,” the company was established to provide reliable, high-quality filters and additives for Cummins, Powerstroke, Duramax, and EcoDiesel trucks, cutting out the middleman and ensuring affordability. Based in small town Ohio, Doc’s Diesel serves customers nationwide, boasting a new warehouse and a rapidly growing grassroots team. Renowned for its rigorous SGS-tested products, swift delivery, and exceptional customer service, Doc’s Diesel embodies hard work, big dreams, and family values, making maintenance easy and trustworthy. You can learn more at DocsDiesel.com.