If you’ve ever tried to remove a stuck bolt, then you know how annoying such a situation can be. But what if we told you there’s a liquid that makes removing jammed nuts effortless and safe?
Penetrating oil doesn’t just ease the process of removing nuts; it’s used as a rust penetrant, and it’s great for loosening hinges and performing a whole range of other functions. For that, it’s seen almost like a magic potion.
This post seeks to help you find the best penetrating oil by listing the top 10 products in the market at the moment. We will also show you the factors to consider, so you’re able to choose what suits your needs.
Need a quick decision? Here’s my top 5 Penetrating Oils picks:
What is Penetrating Oil? Why do you need it?
Also known as penetrating fluid, penetrating oil is a kind of petroleum-based lubricant that has a very low viscosity that helps it seep into tight spaces.
Viscosity is the measure of a fluid’s thickness or resistance to flow.
There are plenty of reasons why having some penetrating oil on hand is a good idea. First, you can use it as rust penetrating spray when you need to set a rusted mechanical part free, say a nut.
Again, when you badly need a lubricant, and you don’t have the proper product nearby, you can use the penetrating oil.
You can also use penetrating oil to:
- Lessen friction on musical instruments especially the metal-stringed ones
- Remove chewing gum and other adhesives from various surfaces
- Cleaning metal parts
Our Top 10 Best Penetrating Oils Reviews 2021
1. Aerokroil aerosol
At the top of our list is the Aerokroil aerosol, which to many people is the best penetrating oil ever. Click the link and see just how many positive reviews this product has.
If you seek rust penetrating spray that will not let you down, just give this one a shot and see how it literally works wonders, penetrating openings as little as a millionth of an inch.
A version of kroil, Aerokroil eases tension in metal joints and takes away the annoying squeaking sound that items like hinges produce.
Someone dropped gum on your carpet or your wood floor and you’re wondering how to get it off? This product could be the solution you’re looking for.
Just apply some of it, and the gum will get dissolved in a matter of minutes. If you’re dealing with an oil stain or grease, the same product will be very helpful.
Some rust penetrants are avoided because they attack the base metal. What’s amazing about that little aerokroil spray is that it penetrates the rust and gets rid of it without attacking the base metal.
When you’re trying to remove bolts or nuts from rusted metal items, the task might be incredibly difficult as the rust jams the bolts or nuts.
When you apply some Aerokroil, the solvent penetrates the little spaces between the fastener and the hole, and it loosens the rust, thus freeing the fastener and making its removal a lot easier.
Something else we’re sure you will love is the smell. As opposed to other penetrants, which have an irritating smell, Aerokroil smells somewhat like cakes.
This penetrating spray is a little more expensive than most other penetrating oils, but it’s totally worth the price.
- Fights rust
- Frees jammed fasteners
- Smells great
- Safe on metal
- Cleans off greasy dirt
2. Kano Sili Kroil Penetrating Oil
When you want to fight corrosion, there’s one tactic that always works. You see, corrosion hardly happens without water, so, by providing a shield against water, you’re able to put up an effective fight.
In regards to that, the Kano Sili Kroil has an exceptional ability to resist water, and thus when you apply it on a surface, you greatly minimize the risk of corrosion.
Apart from that, the product is a fine lubricant. Regardless of how little space there is, it penetrates into the stuck-together surfaces, breaking down the iron oxide (rust) and reducing the tension and friction in there.
Dealing with a hard to reach tight spot? Tell you what? The product comes with a straw, allowing it to shoot very far and more easily.
The Kano Sili Kroil Penetrating Oil might not be termed cheap, but it certainly isn’t going to break the bank. And, for the awesome functionality it offers, we’d highly recommend the stuff.
It’s a product of the respected Kano brand, and you can use it for a wide range of applications, from loosening bolts to lubricating car moving parts.
If you have used other penetrating oils without the results you desire, just give this product a try and see how it works out for you.
- Great water resistance
- Has a straw for powerful and precision shooting
- Respected brand
- Effective lubricant
3. Liquid Wrench L103 Penetrating Oil – 3 oz
A family-owned company, Liquid Wrench makes some of the best penetrating oil for rusted bolts in America, and the L103 is one of their masterpieces.
When it comes to rust removal, the L103 is the definition of unmatched performance, and over the years, it’s undergone tremendous improvements that have seen it gain a special place in the hearts of both tradesmen and ordinary DIYers.
If you need a good multipurpose penetrant oil that’s able to accomplish a range of functions, then this is the product to get.
Whether you want to lubricate moving parts, free a rusted bolt or nut, unfreeze a lock or get rid of the grease within a pipe or hose, the product will definitely be helpful.
As mentioned before, this penetrating oil is made by a family company. Moreover, it is made in the US, in Charlotte to be specific. You know what that is? An indication of quality.
Even without knowing much about the product, there’s some assurance about quality from the fact that it’s a US-made product, and giving it a shot wouldn’t hurt, would it?
The oil is not like other rust penetrants that have bad, high odors. Instead, it has a very low odor that will not affect your comfort during use.
Ever heard of volatile organic compounds (VOCs)? These are products that have a high vapor pressure even at ordinary temperatures, and for that, they’re regarded as extremely hazardous.
These substances cause irritation in the skin, eyes, and respiratory system, and harm internal organs like the liver, and the bad news is that you can find them in any product from cigarettes to poor quality penetrants.
To avoid them and stay safe, try a high-quality penetrating oil like the L103 from Liquid Wrench.
- Zero VOCs
- US-made product
- Mild odors
- Environmentally friendly
4. B’laster 8-PB – Penetrating Catalyst
B’laster is one of the most well-known penetrating oils in the world; you might have heard of it. The reason for its huge popularity is simple – quality and effectiveness. If you need to loosen corrosion and rust and make its removal easy, you can never go wrong with the B’laster 8-PB.
This penetrating catalyst creeps up those cavities that you deem hard to reach and solves your rust problem while loosening the tension.
If your braking system has become stiff and you’re looking for a quick solution, this product would, without a doubt, be a worthy shot. And not just that; if your exhaust or suspension system is jammed, the product might be of assistance.
A problem that’s commonly associated with penetrating oils is that they evaporate quickly, thus making them ineffective when used to lubricate surfaces.
This B’laster penetrant is different. Its film has the quality of being non-evaporating; it remains on the surfaces, and hence it’s an effective lube.
Perhaps you have an old truck, and you’re looking to revive it. Why waste its fasteners with aggressive removal means like drilling? Just apply the B’laster 8-PB to ease the stiffness so you can remove it normally and easily.
The B’laster brand has been around for more than 50 years, and when it comes to the provision of lubricants and rust inhibitors, it’s a brand that DIYers and professionals trust. You are likely to love 8-PB’s results.
It doesn’t matter if it’s a bolt you want to loosen, a pipe whose greasy inner surfaces you want to clean or a hinge whose squeaking sound you need to take care of; the penetrant will come in handy.
- A non-evaporating film that makes lubrication effective
- Penetrates hard to reach spots
- Respected brand
- Multiple uses – cleaning, lubing, loosening
5. Liquid Wrench L116 Penetrating Oil
As its name suggests, the Liquid Wrench L116 is essentially a liquid wrench; it’s as effective as a wrench when it comes to removing fasteners, only that it’s in liquid form.
The product is manufactured by a family-owned company that has been around for over 70 years, and over time, it has become a favorite tool among tradespeople and DIYers. How? The continued superior performance and innovation.
When you have a stuck nut or bolt, you might be desperate for a solution and might even be considering methods that would require lots of elbow grease. But you don’t have to go through all that trouble when you have the Liquid Wrench L116 on hand.
It’s a powerful, penetrating oil for rust, and despite how tight the fastener seems, the product will make its way in there and free it.
As a US-made product, it gives you some assurance on the quality. And not just that; it’s safe on painted surfaces as well as the environment, and it complies with the law in all the 50 states.
Most rust penetrants and rust fighters don’t have a very pleasing smell, and using them might get you very uncomfortable. If you want comfort using a penetrant, try this product; its smell is only mild.
The product does not work for nuts and bolts alone. Perhaps you have a stuck lock, and you’re wondering what to do with it. Well, try this rust penetrant.
Sometimes, locks will jam due to rust within the system, and when the product takes care of that, your lock starts moving normally again.
- Multipurpose use – nuts, bolts, locks, latches, clamps, fittings, pipes, etc.
- Mild odor
- Safe on plastics and painted surfaces
- Made in the US
- Fights rust and grease
- Trusted brand
6. Gasoila Free All Rust Eater
If you’re dealing with a combination of a rust and jamming problem and you seek the best rust penetrant, allow us to tell you about the Gasoila Free All spray. Whether it’s a hinge, bolt, fence, gate, or any other metal object, this rust removing penetrant will not only remove the rust; it will free the object as well.
Threaded pipe connections, rusted muffler clamps, pillow blocks, tailpipes, locks, and universal joints are a few other examples where the rust eater can be helpful.
Apart from rust, the product is good for getting rid of white and red lead, carbon, graphite, and tar deposits. And if what is troubling you is scale, the rust penetrant will also be handy.
Wondering about the product’s effects on the environment? You’ll be pleased to know that it doesn’t contain silicones or other harsh chemicals, and this makes it safe for the environment. For the same trait of not containing harsh chemicals, the oil is safe for your painted surfaces.
The effectiveness of this penetrant at loosening fasteners makes it unnecessary to use methods like hammering, chiseling, and torching.
Subsequently, you won’t have to waste money or energy getting off fasteners, and you certainly will avoid damaging objects through harmful removal methods like torching and drilling.
You know why it’s called Free All? Because of its multipurpose nature. Talk of bolts, nuts, pipes, hinges, locks, rusted benches, etc., Free All will be helpful.
- Doesn’t contain silicones
- Environmentally friendly
- Safe for painted surfaces
- Multipurpose – removing rust and freeing fasteners
7. Kano Kroil Penetrating Oil
Here’s another penetrating oil from the popular Kano brand. The Kano Kroil features superior chemistry that allows it to lower the surface tension on your rusted or jammed metal items, thus breaking apart the bonds causing the rust or jamming.
Because of its incredibly low viscosity, the solvent is able to reach into the most squeezed spaces, loosening the stiffness and lubing the surfaces so that if it’s a moving or sliding mechanism, the movements progress without hindrance.
If it’s a bolt or nut, removing it becomes a whole lot easier.
There are many effective penetrating oils out there that remove rust and free fasteners, but one issue makes most of them inappropriate – attacking the base metal.
The Kano Kroil is effective against rust, and you know what is even more amazing? The fact that it attacks the rust without harming the base metal.
The product is very efficient when it comes to displacing water, and thus it’s able to prevent further rusting while providing the lubrication needed.
Struggling to remove grease or soap residue from your sink or toilet? Why not apply some of this product? It works great for grease and soap scum. Oh – and it works for hard water residue as well.
- Very low viscosity
- Penetrates the tightest spaces
- Works for pistons
- Removes soap scum and hard water stains
- Doesn’t harm the base metal
8. B’laster 16-PB Penetrating Catalyst
We talked about the B’laster 8-PB, and now it’s time to talk about the other version, the B’laster 16-PB. The two are virtually the same, and the only difference is with the size.
The 8-PB contains 7 ounces of the penetrating oil, while the 16-PB contains 11 ounces. So, the former is for when you need just a small amount of penetrant to remove rust or free a few nuts and bolts, while the latter is for when you need more penetrant.
Actually, if you have many tasks that need lots of penetrant fluid, we’d advise you to buy several packs of the 16-PB penetrating oil.
Whether your metal parts are rusted or frozen, the solvent is likely to work.
You might have heard that most penetrating oils evaporate quickly, leaving behind solids, and this renders their lubing ability poor. That’s why you’ll hear many experts recommending that you use such oils for temporary lubing only when you can’t get your hands on a proper lube.
Well, this product is quite different. It is a non-evaporating lubricant that will stay on there as long as any other good lube would.
The product is from the B’laster brand, and keeping in mind that this is one of the best brands specializing in rust removal and lubrication products, the PB-16 can be trusted to do what it’s meant to do. Moreover, it’s got plenty of great reviews on Amazon; check them out.
- Removes rust and grease
- Frees frozen parts
- A non-evaporating lubricant
- Easy to apply
- From the trusted B’laster brand
Many of you might already have heard of WD40. It’s one of the handiest multipurpose products ever, with applications ranging from lubricating metal surfaces to removing rust. It actually has over 2000 uses.
As its name indicates, WD40 (stands for water displacement 40) is great for displacing moisture. And as you might already be aware, water is needed for rusting, so WD40 is an excellent solution to a rust problem.
The can comes attached with a permanent straw, which increases the precision with which you dispense the solvent.
One of the most amazing facts about this product is the design of the can. It’s made such that you can spray the fluid two ways. You can flip it down to spray or flip it up to release the fluid as a stream.
With the spray function, you can apply it to hard to reach spots, and with the stream, you’re able to move fast.
The multipurpose nature of WD40 spreads to the number of items you can use it on. Whether you’re dealing with wheels, hinges, engines and motors, nut and bolts or bike chains, the product comes in handy for fighting rust and freeing the stuck parts.
Worried about harmful effects? Well, here’s some insight on that – this particular WD40 product doesn’t contain kerosene, graphite, CFCs, or silicone. Thus, you got nothing to worry about.
- Multiple functions – lubing, removing rust, protecting, penetrating and loosening, etc.
- Free of harmful chemica
- lsInnovative design – spray or release it as a stream
- Straightforward use
10. 3-IN-ONE Multi-Purpose Oil
Having been around since 1894, the 3-IN-ONE Multi-Purpose Oil is the oldest penetrating oil on the market. During the over 120 years that it’s been around, it has become and stayed one of the most loved, most used penetrating oils.
This multipurpose drip oil is usable by both DIYers and tradesmen, applying to a wide range of functions, including lubricating moving parts, cleaning and protecting tools, and clearing and preventing rust.
Whether you’re dealing with a stuck nut or bolt, or a jammed bicycle chain or wheel perhaps, you will find the penetrating lubricant very useful.
Moreover, the product fits you whether you need a penetrating oil for home, shop, automotive, or marine use. All you need to do is get the size that suits you.
Those who are looking for precision and ease of use will find this product very appropriate. First, it comes with a drip spout that makes it super easy for you to apply it without wastage through splatter or overspray.
Again, the new packaging comes with an indicator strip, which lets you see how the liquid is getting used.
The bottle features a squeeze design. This gives you control over the amount of liquid you’re going to dispense, and it’s another trait that gives you precision while helping you avoid wastage.
Effectiveness and ease of use are the two major pros of this penetrating oil that make it truly valuable.
- Squeeze bottle
- Pour spout
- Indicator strip
- Old, trusted brand
- Multipurpose use
Things to Consider Before Buying a penetrating oil
Many people go to the shop and ask for penetrating oil. The sender hands them a bottle, and they pay and leave without taking the time to think about the product, as they assume one penetrating oil is like any other.
Here’s the deal – penetrating oils are not the same, there are many brands out there, some being good and some being bad. Let’s look at some of the features and factors you need to consider to find the penetrating oil that fits you excellently.
Type of penetrating oil
There are four main types of penetrating oil, including synthetic, straight, micro dispersant, and emulsion. Each of them has its pros and cons that could make it suitable or unsuitable for your targeted uses. Below, there’s a whole section on the types of penetrating oil available. Be sure to check it out.
Viscosity refers to the thickness of a fluid. A high-viscosity fluid is one that is very thick, and for that, it flows with difficulty and has poor penetration capability.
A low viscosity fluid, on the other hand, is a thin fluid that flows easily (water is a good example) and has high penetration capability.
If you need a good penetrating lubricant that will work perfectly for loosening rusty objects, go for one with the lowest viscosity.
Ease of Use
This is a most important factor if you’re to have a good experience using penetrating oil. When shopping for it, please make sure the oil can work straight out of the package without having to treat it in any way.
Ability to tolerate heat
As mentioned earlier, different penetrating oils have different abilities to tolerate heat. You think you might need to use the product on hot items? Get a synthetic, fire-tolerating penetrating oil.
Ask yourself what you need the penetrating oil for. You see, penetrating oils have ranging chemical compositions and for that, what one penetrating oil might be able to achieve mildly can be done to perfection by another penetrating oil.
For instance, some penetrating oils are resistant to fire, and if you try using them to separate hot metals, they will not work. Others are not fire-resistant, and they will work for that purpose.
Again, while one penetrating oil might be safe for a certain application, another brand might have compounds that would be damaging for that application.
If you love the environment or will be working in an area that is sensitive, it’s only natural that you will want to get a product that doesn’t have adverse effects on it. In that case, an eco-friendly penetrating oil will be handy.
The price normally ranges between 5 and 25 dollars per bottle. We even featured the 8-oz 3-IN-ONE Multi-Purpose Oil, which is for those who are on a very tight budget and looking for the most inexpensive option. It’s currently going for under 5 bucks per 8 ounces.
However, keep in mind that for manufacturers to use high-quality ingredients, the price has to be high.
That’s why we’d recommend going for a more expensive option like the Kano Aerokroil (the first item in the review), which is presently going for around 20 bucks per 10 ounces. Rest assured, it will work excellently.
The Types of Penetrating Oil
Okay, we mentioned that when you’re shopping for penetrating oil, one of the factors to consider is the type of penetrating oil it is.
We also pointed out that there are 4 main types: synthetic, straight, micro dispersant, and emulsion. Now is the type to dig deeper and see what each type has to offer.
Micro dispersant oils are made of natural or synthetic oil bases holding the solid lubricant particles within them. Some examples are graphite and polytetrafluoroethylene.
A micro dispersant penetrating oil is good, but if you’ll be using it on hot surfaces, you’d better reconsider getting it as its fire resistant.
A straight penetrating oil is a non-emulsifying oil that is manufactured from a base mineral lubricant with a fat, an ester or an extreme pressure additive like chlorine or sulfur.
If you’re looking for penetrating oil to use in a mechanical application, say to fix or clean motor parts, then a straight penetrating oil will be helpful.
Synthetic or Semi-Synthetic
These are made up of synthetic compounds like di-esters, chlorofluorocarbons, silicone, and poly-glycol.
Emulsion penetrants are basically water-soluble fluids with high water content and thus a low concentration of less than 10% most of the time.
Those are the four main types, but there’s another way in which penetrating oils can be grouped:
- Penetrating oil liquids – best for removing jammed fasteners
- Penetrating sprays – best for cleaning metal parts and removing adhesives like chewing gum.
Top 3 Penetrating Oil Brand in The Market?
Kano Labs is undoubtedly one of the best rust penetrant brands in the world. Based in Nashville, US, the company makes the Kroil series of penetrating oils, which are known to be some of the best products of their kind.
The Aerokroil is not the number one item on our review for nothing; it’s very effective and truly exceptional in regards to performance and safety.
From the quality of the products to the manner in which the support team handles issues, the Kano Labs brand is totally worth buying from.
The Liquid Wrench company started in a rather unusual way. Its founding takes us back to 1924 when Mr. Blumenthal needed his car’s radiator repaired.
A Charlotte tinsmith used a sort of “magic potion” to repair it, and an impressed Mr. Blumenthal signed a contract with the tinsmith, and the Liquid Wrench was born.
Today, the family-owned brand makes some of the finest rust penetrants in the world, and anyone who needs a truly efficient, safe rust penetrant shouldn’t hesitate to buy from it.
Started in 1957, B’laster is a rather familiar brand that is based in Cleveland. It’s arguably the best-selling penetrating oil brand in the US.
The reason for its vast popularity is easy – its products are effective. Whether you need to loosen rust and free metals or just to clean grease off a surface, a B’laster penetrant will likely do the trick.
Different Uses of Penetrating Oil
By now, we bet you have noted a few uses of penetrating oil. For instance, for cars, they can be used for removing rusted nuts and bolts and for performing other functions like reducing the noise in hinges and suspension systems.
Penetrating oils are also helpful when it comes to protecting metal parts from corrosion.
Actually, when talking about penetrating oils, we are talking about three major functions – protection, the displacement of moisture, and lubrication.
As a form of protection, the oil provides surfaces with the power to resist agents of rusting, like water and salt.
When using it as a lubricant, the oil works to reduce the friction and heat as well as the noise between two metal surfaces, say a hinge or a bolt and the hole where it is fastened.
Here are some parts where you can apply a penetrant:
- Air tools
- Electrical terminals
The Kano Aerokroil (the first product in our review) is a good example of a penetrating spray that can handle all the said functions.
It not only improves performance but also the life of moving parts. And apart from being good for automobiles, the oil works excellently on farm equipment, hand tools, firearms, air tools, etc.
To learn more about it, just scroll to the review section and check out the first item on the list.
In summary, these are the standard uses of penetrating oil:
- Repelling water
- Fighting corrosion
- Loosening fasteners
- Lubricating moving parts
The low viscosity of the oil allows it to reach into tight spaces without resistance. The best part is that with the oil, there won’t be that annoying squeaking noise.
When you’re dealing with a hard to reach spot, it’s better to use a penetrating spray rather than a liquid.
How does the oil repel water? Here’s how that works – the oil has low viscosity and hence when applied, it expands on the surface to create an even coat that repels water.
In addition to these uses, penetrating oil has certain non-standard uses, including removing:
- Acrylic paint
- Spray paint
- Dripped varnish
- Stickers, chewing gum, and other adhesives
Advantage Using of a Penetrating Oil
The benefits of using penetrating oil are limitless. Assuming you have a stuck nut or bolt, a penetrating oil will come in handy. How?
Penetrating oils have low viscosity. Viscosity is the ability of a fluid to resist flowing. It’s basically depends on the fluids thickness, so that thick fluids like honey have high viscosity while thin fluids like water have low viscosity.
With their low viscosity nature, penetrating oils are able to reach tight spaces and lube the surfaces.
Rust happens to be one of the reasons why fasteners jam. Penetrating oils get in there and loosen the rust, thus freeing the fastener.
So, those are two function – lubing and fighting rust.
If you have a greasy sink, pipe or anything else that’s becoming hard to clean due to the grease, try some penetrating oil. It breaks down the bonds and makes wiping off the grease much easier.
Rather than using expensive/complicated means of removing the fastener, like drilling or torching, try penetrating oils. Amazingly, they are pretty cheap, going for less than 20 bucks most of the time.
In summary, the advantages of using a penetrating oil are that the oil:
- Reaches hard to reach spaces
- Loosens rust and prevents further rust formation
- Lubricates objects
- Prevents damage to your objects
- Are inexpensive
Frequently Asked Questions (FAQs)
1. How does penetrating oil differ from lubricating oil?
While lubricating oil is used to protect and prevent parts from becoming stuck, penetrating oil is used to free stuck nuts, bolts, and other parts, and it’s especially helpful where those parts are rusted.
2. Are penetrating oils flammable?
The flash point of most penetrating oils are low, and that means their flammability is high. But some products, like most of the ones on our review section, have a high flash point, and thus low flammability.
Flammability rating is important because when using the product on hot surfaces or near fires or sparks, you don’t want the oil to catch flames.
3. I’d like to clean my barrel. What penetrating oil can I use?
Try the Aerokroil penetrating spray. Once you’re done with your shooting adventures, wet the barrel with the Aerokroil spray, allow it to sit for an hour or so, and push a patch through it to remove the grit.
4. Is WD-40 a penetrating oil?
WD-40 stands for 40th water displacement formula, and it’s one of the best products that are used for a wide range of applications. As a penetrating oil, WD-40 penetrates narrow spaces, cleans them, displaces moisture, lubricates and fights rust.
5. Do penetrating oil prevent rust formation?
Apart from lubricating and cleaning parts, a good penetrating fluid contains rust and corrosion inhibiting properties.
6. Does penetrating oil harm plastics?
Ordinarily, penetrating oils don’t have damaging effects on plastic. Nonetheless, there are certain sensitive forms of plastic that may be dissolved or damaged in other ways, and we recommend that you avoid using a penetrating lubricant on polyurethane.
We hope this guide has helped you find the best penetrating oil for your needs. Most of the products discussed are inexpensive, going for a few bucks, and they’re also very effective at penetrating your stuck surfaces and freeing them.
Aerokroil is a little more expensive than the others, but if superior effectiveness is your priority and your budget allows it, we’d recommend you go for this penetrant.
You’ll be much more pleased with the results, and after all, we believe, 20 bucks won’t break the bank. If you’re on a very tight budget, the other products are still pretty good, only not as good as the Aerokroil.
Follow our links to find out the exact prices of the products on Amazon.