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The engine is the heart of your car and everything needs to flow through it properly. Over time, it is bound to get clogged up with dirt and deposits, which will negatively impact its performance. The main purpose of an engine flush is to clear out the contaminants left inside to get things running smoothly again.
There are a host of benefits directly associated with using an engine flush. Beyond removing the deposits and dirt inside the engine, it also helps to clean out parts of the engine that are hard to access, keep the new motor oil cleaner, improve your fuel economy, and minimize emissions.
However, if you have never bought a product like this one, it can feel slightly daunting when choosing one. We created this guide to give you a comprehensive overview of some of the best products currently on the market.
The Best Engine Flush
When you need to flush out the engine system of your gasoline or diesel hub, this product works well for either. It has been highly lauded for a cleaning effect that is both quick and gentle, so you don’t have to worry about any damage from occuring.
It is very easy to use, and as soon as you start it will get to work enhancing the combustion process and getting your engine performance back to the recommended level. Whatever engine oil you are using, this product is fully compatible with all that are readily and commercially available. A few benefits include dissolving sludge, preventing corrosion of metal, and improving oil lubrication.
Easy way of cleaning and flushing oil systems
Removes harmful deposits from the engine
Simple application method
Regularly voted best brand in its field
- BrandLiqui Moly
- Weight 2037
If you need a lot of engine flush, here is a 12-pack that you can use prior to every single oil change. Many contaminants can gather in the internal parts of your engine that can negatively impact performance, including sludge, which this product helps to clear.
It is a simple product to use, and you can treat your engine in just five minutes. And once you are done, the oil will flow around the system much easier. This is a professional-grade product that is perfect for clearing the kind of engine blockages that can be directly linked to slow driving in towns and cities.
Promotes reduced oil consumption
Destroys sludge, deposits, and contaminants
Suitable for regular car owners or professional technicians
Takes just five minutes to treat engine
- Model MF3-12PK
- Weight 25 pounds
Formulated to reduce engine friction and wear, it also works to reduce oil temperature in modern complicated engines. You can use it in both diesel and gasoline engines. When you start using it, you should notice an improved fuel economy thanks to the reduction of engine friction.
Promising to protect and extend oil life by 30 percent, this product saves you from having to change the oil in your car so often. As well as reducing the hot running temperature inside your engine, it helps to ensure smoother running.
Minimizes friction and wear
Improved anti-friction and anti-wear properties
Inhibits oxidation to improve engine life
Proven technology and trusted brand
- Weight 2.3 pounds
A very popular product for both gas and diesel engines, the specialized engine sludge flush comes with anti-friction metal treatment technology. The protective layer created by this heat reduces the damaging effects of heat and friction.
In hotter running engines, this type of temperature reduction is even more important. All you need to do it pour it straight into the engine crank case.
Super lubricating on both gas and diesel engines
Forms protective layer on your engine after application
Effective under extreme heat
No solid particles contained within the formula
- BrandProlong Super Lubricants
- Model PSL11000
- Weight 15.2 ounces
Whether you have a gas, diesel, or even a supercharged engine, you can use this engine flush to improve the performance of your vehicle. Whether your engine uses conventional or synthetic motor oil, you can use it comfortably.
There is plenty of sludge, varnish and gum that accumulates inside your engine unless you take the time to clear it out properly. This motor flush helps to get rid of all of the above so the oil can flow freely around your engine.
5-minute engine cleaning process
Professional grade motor flush
Offers improved oil circulation
Promotes reduced oil consumption
- Weight 2 pounds
Another engine flush from Lubegard, this one also works for both gas and diesel engines. It contains no harmful solvents to unintentionally damage parts of your engine. Once you have used it, your engine is prepped for some fresh oil to be put inside.
The ‘how to use’ guide is written clearly in the product description to help you in the application process – though it shouldn’t present you with too many problems. After you have finished, the oil circulation should be so much better, which will improve the performance of your vehicle.
Cleans gums, varnishes, and deposits
Improves oil circulation
Prepares your engine for fresh oil
Premium synthetic blend
- Weight 15 ounces
This product has the approval of professional mechanics and DIYers alike. Even if you are just a regular car driver, there are plenty of benefits to be gained from using it. Straight away, it gets to work dissolving and cleaning fuel and oil residue.
Users like this product for its ability to clean fuel and oil residue and deposits. You just need to pour it in your oil crankcase and the magic will start to happen!
Works to dissolve oil deposits in crankcase
Cleans injectors and passageways
Safe and effective
- BrandSea Foam
- Model SF-16
- Weight 8 ounces
If you have sludge deposits in your gas or diesel engine system, this cleaner works to effectively break them down. In fact, it gives a good clean and rinse to the entire engine, so you are left with a system that operates better than before.
One of the things that people are most concerned about before they use an engine flush is whether or not it will be easy to use. Well, with this one, all you need to do is add the contents to warm motor oil before your next change.
Cleans oil sludge and deposits
Compatible with all types of engine oil
Protects against loss of compression
- Model 1390321-400-05-000
- Weight 15.2 ounces
Using an anti-carbon effect, this cleaner has an anti-carbon effect and immediately gets to work getting rid of contamination and engine sludge. It works with all types of engines, including those that are turbo supercharged.
Once you have used the product, you can expect a thorough cleaning of the whole oil system of your car. It promises to safely clean your engine of all contaminations to get it back to its technical purity.
Compatible with any application
Cleans engine system back to technical purity
Can be used for quick or deep cleaning
Universal for all types of engine
- Model XA 40613
- Weight 10.4 ounces
Best Engine Flush Buying Guide & FAQ
Now that you have finished about reading about the best engine flush cleaners on the market, you may still feel like you need a little more information. Well, we are going to cover a lot of points in the next section to help you make up your mind. After this, we will follow up with a section of frequently asked questions to cover everything else that has been left up in the air.
Features to Consider When Buying an Engine Flush
Before you decide on the right engine sludge flush for your vehicle, there are plenty of different factors to weight into account. After all, they were not all created equal. So, here are a few pointers on what you should be looking out for.
Engine oil flushes are made up of different additives – and not all of them are the same. You need to work out what combination of them is going to work best in your vehicle. Engine flushes are usually potent substances, which means that you cannot leave them in your vehicle for too long without the risk of potential damage. A component that should feature across the board is detergent as this gets rid of the accumulated sludge and other deposits. Often, these are alcohols or acids. Then you have the dispersants, which break up solidified deposits. They dislodge them to be dissolved in the detergents.
Next, you have antiwear, which is one of the nonessential components of engine flushes. It may use carbon or metal to stop wear and tear in your engine. Generally, these are weaker than what you find in specialized antiwear products. Lubricants are also commonly found in engine flushes. These work to reinforce the clean oil rather than making it perform better. The least common that you are likely to find are rust-inhibitors as the acids and alcohols found in many engine flushes don’t work well with the agents. They are more likely to be found in milder flushes.
Many of the engine oil flushes that we have discussed in this post work well with all types of engine, but this is another factor that is worth considering. Check for oil or diesel compatibility as a starting point. For example, tuned engines that contain non-standard materials may be damaged by some of the harsher engine flushes out there. You should also consider whether or not the flush is compatible with the oil as you will often need to mix them together. Nowadays, most of the top brands are formulated to be compatible with all types of common motor oil, but this is something that is still worth checking before purchase.
- Time Required
Different motor flushes have different guidelines when it comes to how long they need to kick into action. Some will take as little as five minutes, while there are others that need 15 minutes or longer to dissolve the harmful engine particles. Bear in mind that you should stick to the recommended time suggested. Otherwise, it is more likely that some sort of harm could befall your engine.
- Price Point
If you are on a tight budget, don’t just look at the actual bottom line cost – you should also consider the typical number of uses that you can get out of a bottle. Also, there are the bigger multi-packs out there that may prove to be better value for the money that you are investing.
- Safe and Easy to Use
You don’t want to risk causing any unnecessary damage to your engine, but some flushes cause unnecessary wear to the engine. You should be looking for a neutral product that is not going to damage the engine’s internal parts. Otherwise, this could cause a sharp decline in the overall performance of the engine. You also need to consider ease of use as a main point. The majority that we have discussed above don’t require any complex machinery like an engine flush machine. You should consider your mechanical abilities and any constraints on your time that are holding you back before you choose the product that is right for you.
When you are using a motor flush, you want it to work efficiently. Some of them are made for professional standard use, whereas others are mainly for DIY usage. Whichever flush you choose, you need it to have the strength to remove tar, sludge, and anything else that you don’t want there. Some engine flushes even have enhanced properties such as the ability to increase the life of the oil in your car by around 30%.
Why You Should Use Engine Flushes
There are a number of reasons why using an engine flush may well prove to be worthwhile. Over time, all sorts of debris can build up in the area, and a proper flush is designed to bring your engine back to increased efficiency. The build up of sludge and debris can end up clogging up your oil passages, which will then limit the flow of oil around your vehicle. Gradually, you may start to notice a reduction in the horsepower of your engine. Also, fuel economy is likely to get worse as well. Engine deposits are much more likely when you only use your car for short trips and stop-start city driving. This is due to the oil not heating up and evaporating moisture.
Of course, there are other ways to improve the performance of your car engine such as regularly changing the oil and using a quality oil in the first place. But an engine flush can just be another tool in your arsenal that you use from time to time. Here are some of the other main reasons why it can be so useful.
- Prepare the Engine for Fresh Oil
Before you put any fresh oil in your car, flushing out the engine removes any contaminants that are clogging it up. This way, you are not letting the new oil can contaminate with anything that shouldn’t be there and it is free to perform in the way that it should. Without the flush, the fresh oil that you put in is likely to not last as long as it should.
- Clean Hard to Access Parts of the Engine
Cleaning out your engine is not a straightforward task without tearing it to pieces. And this is obviously not a viable option on a regular basis. A decent oil flush takes care of the job of cleaning without any need to take anything apart.
- Improve Fuel Efficiency
Nobody likes having to go back to the gas station more often than strictly necessary! By using an engine flush, you help to prevent the oil from becoming too viscous. If this happens, more energy is needed for it to be pumped through the engine properly. Also, sludge and other contaminants can increase resistance, which requires more fuel to overcome. By ensuring everything runs smoothly, you go a long way towards maximizing fuel efficiency.
- Reduce Emissions
A good-quality engine flush will free the rings that get stuck in the engine, thereby reducing oil consumption. And when this is lowered, emissions will be reduced, in turn. If you are environmentally conscious at all, you should be looking for ways that you can reduce your carbon footprint, and this is certainly one of your options.
- Lowers Heat
Too much heat is bad for both your engine and the oil that it uses. While engine efficiency will be reduced, sludge and other deposits will prevent the engine from dissipating heat in the way that it should. Flushing out your engine ensures proper heat management, which improves both efficiency and oil lifespan.
Types of Engine Flushes
The main consideration when you are choosing the best engine flush cleaner is making sure that it is compatible with your engine. As we already mentioned, many of the ones above have universal compatibility, but there are some that are designed to only work with specific engines. The last thing that you want is to risk any harm coming to your engine, so you should either choose one which is specifically compatible with your engine or one that works universally.
The basic function of an engine flush is to remove gunk, sludge, or any other unwanted particles that may be clogging up your engine. However, there are others that are designed for more specific purposes. Some will protect the parts that are exposed to salt, whereas others not only clean, but they also leave a protective layer behind. Others are made to prevent overheating in the cooling systems. You should choose the right one that matches your vehicle’s needs.
Tips for Using Engine Flush
If you are going to perform an engine flush, you should identify the signs that your vehicle actually needs one. And you should always use a recognized brand name product from a manufacturer who you can trust. If you are not confident taking care of the job yourself, it is worth going to a recognized professional to make sure that everything is taken care of properly.
Best Engine Flush FAQ:
Q: What is an engine flush?
A: An engine flush is an aftermarket chemical additive product that you put into your car engine to get rid of anything that accumulates inside that shouldn’t be there including sludge and deposits. It gets to work when you put it in the engine’s oil filter port and leaving the engine to idle for between 5 and 15 minutes. When you drain the oil, the flush will take out the other gunk along with it. You can then change the filter and put in some fresh oil, so you are ready to get driving once again.
Q: How do I know I need an engine flush?
A: An engine flush can be useful in a wide range of situations. The easiest way of noticing that there is sludge in your engine is to check whether or not the dashboard light in on. It could be the check engine, or your oil change light may come on sooner than you would have otherwise thought. Another way that you can tell is by glancing under the hood. Check for oil spatter or engine sludge. If you want to be even surer, you can remove the oil cap from the can and check in there – possibly using a torch if you need one. If there is any sludge in the pan, you may find more of the same in the engine too.
Q: Is it safe to use an engine flush?
A: Using an engine sludge flush is a safe process as it is a product that is specially designed to get rid of harmful particles that are present within. Many of the flushes that you can buy are neutral, meaning that no harm will be caused to the engine’s internal parts. When you notice that an engine is not running smoothly, you can use a flush to remove the other particles. Engine flushes are generally neutral, so you shouldn’t need
Q: Can I flush engine oil by myself?
A: Most modern engine flushes are designed for easy use, so you should be able to do it yourself. If you are unsure, it is worth going to the professionals to have them do it for you.
Q: How long does it take to flush my engine without a machine?
A: It depends on the individual engine flush, but most of them get to work in 5 to 15 minutes.
Q: How often should I flush my engine?
A: There is no set amount of time that you should leave before flushing your engine again, but once you notice the performance of it drop due to rough running, excessive noise or fuel consumption. An alternative is to have a professional check the condition of the engine. Older engines are likely to need increased flushing as waste will probably accumulate in a bigger way.
Our Top Pick
Returning to the number one product on the list, we have this highly rated engine flush which works to clean out the system of either oil or diesel engines. The cleaning effect gets to work rapidly, but it is also gentle to not damage your engine. Plus, it is a product that is very simple to use. For these reasons and more, we have ranked it as the best engine flush.