How To Remove Engine Sludge

Engine sludge is an issue that develops over time. If you notice your engine’s valvetrain components are starting to make noise, your oil pressure is slowly dropping, or the oil warning light illuminates while driving, it might be due to engine sludge. But how do you get rid of this greasy buildup in your engine? Are there ways to prevent it? Let’s find out.

What Exactly Is Engine Sludge?

Before we get into how to get rid of it, it’s helpful to know what engine sludge is. When engine oil comes into contact with heat and oxygen, it starts to change from a dark liquid into a thicker, viscous substance. The resulting contaminated oil tends to stick to the engine parts rather than flow through as it should.

The gelatinous, oxidized oil most commonly forms around the engine’s crankcase and slowly builds up over time, mixing with dirt, grit, and other contaminants over time. This results in engine sludge, also known as oil sludge, which can block oil passages inside your engine, leading to a host of other problems down the line.

How To Remove Sludge From Your Engine

Engine sludge is essentially gunked-up oil, so removing it from your engine is a more complicated version of your typical oil change. To get rid of engine sludge, you need to first get it out of your engine and into the oil sump. Here’s how to do that:

Use an Engine Additive

The first thing you’ll need to do is thin the engine sludge enough so it flows out of the engine. There are different engine additives on the market that are formulated as engine sludge removers. Park your vehicle on a level surface and pour the treatment into the engine. Follow whatever instructions are included with the additive for the best results.

After adding the solution, run your vehicle for 10 to 15 minutes to warm up the engine. Don’t actually drive the vehicle around in this state, just get the engine up to temperature. The engine treatment should liquefy the sludge in the motor, allowing it to mix with the rest of the dirty oil for easier flushing.

Keep in mind that these additives might need to be used on the engine more than once. If the sludge buildup is particularly bad, you might even need to use them more than once. If your engine sludge problem is severe, engine additives may not work at all. We cover how to deal with extreme cases of engine sludge later on.

Drain the Dirty Oil

Once the engine has warmed up enough, it’s time to drain the dirty oil and liquefied sludge. Drain the dirty oil as you usually would by removing the oil pan’s drain plug and letting the liquid run into a drain pan.

Install a New Oil Filter

Remove the old oil filter with an oil filter wrench and allow the oil to drain out of the system. Place some clean oil on the gasket to create a solid seal on your new filter as you install it. Turn the filter clockwise with your hand to tighten it into place.

Add Fresh Motor Oil

Once the old oil is drained and the new filter is in place, you can reinstall the drain plug and pour in fresh motor oil. Don’t forget to make sure the oil grade is compatible with your system by checking your vehicle’s service manual. Using the wrong motor oil can encourage more sludge buildup and damage your engine.

Once you’ve poured in the new motor oil, check the oil level with the dipstick. The oil level should be between the ADD and FULL lines. If it isn’t, pour in more oil, taking care not to overfill the system. Tightly screw on the oil filler cap and test drive your vehicle to see if all your efforts produce results. Your engine should be running better now.

Oil has 3 properties: clean, lubricate and cool. Manufacturers are lengthening the mileage your vehicle can go by twice as much now. Mechanics used to recommend oil change intervals every 3,000 miles for vehicles using conventional oil and 5,000 miles for those using synthetic oil. Now manufacturers are saying you only need a change every 12,000 miles.

I have a 2012 sienna and it takes full synthetic 0w20. The mileage for oil change is 12k. I change the oil every 6k because Toyota will not take care of me down the road if I end up with sludge buildup or an engine failure from old oil.

–Anthony Harlin, ASE Certified Master Automobile Technician

Extreme Engine Sludge Solutions

If the engine sludge buildup is so bad that it starts to cause oil starvation, it’s a bad idea to run your engine at all. An engine oil flush would require you to run your engine for a few minutes, so using engine additives to attempt a flush might be risky. In these cases, you might need to remove the oil pan and clean out the engine sludge manually.

This manual engine sludge removal process should be fairly simple if the oil pan is unobstructed. Take the oil pan out, remove the engine sludge by hand, and clean up the oil pan and oil pump pickup so any new oil can easily flow through the system. Replace the oil pan gasket before reinstalling the pan and refill your oil as needed. While this won’t clear out all the engine sludge, it’ll allow your engine to reach the minimum required oil pressure for a proper chemical flush and treatment. Remember though that this only will do anything if you’re starting to have low oil pressure warnings caused by sludge, not a bad sensor. This would be from the oil pickup being clogged.

In even more severe cases, the engine might need to be partially disassembled to remove the engine sludge. At that point, it’s probably best to have a trusted mechanic handle the process instead of learning how to remove engine sludge by hand yourself.

How To Prevent Engine Sludge Buildup

To prevent engine sludge buildup, it’s best to keep up with your regularly scheduled oil and oil filter changes, use high-quality oils and oil filters, and avoid shorter trips when you can. Also be sure to warm your engine completely before turning it off and avoid driving in harsh conditions. In addition, you can try switching to a full synthetic oil to lower the chances of engine sludge buildup.

Preventing engine sludge buildup is a lot easier than solving it, and following the proper oil change intervals is a very large part of this. As we’ve discussed, removing sludge from an engine can be a rather difficult process depending on the problem’s severity. While it’s good to know how to remove engine sludge, it’ll always be best to avoid it entirely with the proper precautions.

Where to Get a New Oil Filter and Fresh Motor Oil

If there’s one thing you should never ignore, it’s engine sludge. Sludge can cause all sorts of problems for your engine, including increased engine noise and overheating. In the worst-case scenario, it can even cause complete engine failure, which can require a full engine replacement. The good news is you can avoid all that by removing engine sludge with the right tools from CarParts.com.

At CarParts.com, you can enjoy high-quality oil filters and motor oils at unbeatable prices. Our price match guarantee ensures that you get only the best deals. If you find a competitor advertising the same product at a lower price, let us know and we’ll either match or beat that price on the spot! We’re committed to giving you the best shopping experience possible, so don’t hesitate to reach out to our customer service staff who are always ready to help you.

Don’t wait until the sludge causes irreparable engine damage before getting rid of it. Check out our selection of high-quality oil filters and motor oils at CarParts.com and order today!