Is Liquid Wrench The Same As WD-40? Get To Know The Difference!

Liquid wrench differs from WD-40. Both are categorized as penetrating oils but serve different purposes and are made of distinct materials. WD-40 is a lubricant and a protectant, while a liquid wrench is exclusively penetrating oil. Besides, liquid wrench gradually seeps through the tiniest fissures and openings to loosen rusted-together parts, while WD-40 is a water displacement treatment intended to leave a persistent rust-inhibiting coating once used.

Although they have a couple of similarities, their differences stand out. Read below to understand more.

Is Liquid Wrench The Same As WD-40

Liquid Wrench

A liquid wrench is used for loosening rusty nuts, bolts and screws, as well as lubrication. It has high lubricity, high solvency, low viscosity, and low surface tension, allowing it to cut through even the toughest of rust. 

A liquid wrench is also prepared in six different formulas, with each being used on specific materials like windows. These formulas allow it to be very versatile and usable over a wide range of materials. However, good as it may seem, it has a downside. 

Benzene is one of the raw products used to make liquid wrenches along with other highly toxic products. Acute exposure to a liquid wrench can cause severe damage to the lungs and the human body at large. Therefore, if you were to use a liquid wrench, you must be well protected to prevent contact that may be hazardous.


WD-40, on the other hand, is hygroscopic and should not be used on materials that may rust, for example, a firearm. Apart from being a rust inhibitor, WD-40 has other uses like removing scratches on a car, removing labels from plastic and glass, removing gum from hair, displacing water from electrical connections and other components and eradicating wasp’s nests. 

WD-40 is also highly effective in serving its purposes and is classified as safe penetrating oil compared to liquid wrench. WD-40 is quite safe for human use as it contains no toxic materials and has no bad effect when in contact with human skin. Incase WD-40 is not affordable or cannot be found, an alternative of a homemade mixture can be used. 

The mixture contains one cup of water and three cups of sunflower or olive oil. Once well mixed, the mixture is good for use and quite effective, just like WD-40. WD-40 has properties like thin and runny hence only acts as an immediate lubricant. These properties attract dirt and dust and should not be used with anything you want to keep clean.

What Should I Not Use WD-40 On?

WD-40 may attack plastic and lacquer, which is insulation on magnet wires in motors. This makes it unusable with drive chains, gears and locks. On the application of WD-40 as a lubricant, it acts as an abrasive and gums up the action with time. On the other hand, the liquid wrench is safe to use on metal, painted surfaces, plastic and rubber.

Which Is Better Penetrating Oil Between A Liquid Wrench And WD-40?

Although WD-40 is classified as penetrating oil, it is more of a corrosion inhibitor. Nonetheless, it is quite far from the top of the list of penetrating oil, and there are many better options. Liquid wrench, on the other hand, is top in the list of penetrating oil. WD-40 appears as one brand, while the liquid wrench has six formulas. Some of the liquid wrench formulas include silicon-based as well as cerflon based. Each formula appears in a certain state raging from liquid to paste and is used on certain materials depending on their composition.

What Are The Uses Of WD-40?

WD-40 can be used for mechanical engineering as well as several home use hacks. Its ability to dispose of water makes it very effective at home for hacks that require a dry environment. For instance, removing gum from hair requires something to dry the gum making it less sticky. The application of WD-40 displaces the water, making it possible to lift the gum off the hair without a struggle. Gardeners also use it on their gumboots to avoid carrying a lot of mud when working in muddy areas. Liquid wrench, on the other hand, is used solely for mechanical purposes.

How Can You Differentiate WD-40 From Liquid Wrench?


WD-40 contains silicon oils that have a bad smell that has to be masked. Vanillin, a popular aroma chemical used mostly in perfumes, is used to mask the odor. Thus, after the use of WD-40, a good smell is left lingering in the environment. On the other hand, a liquid wrench has a terrible smell that lingers for days after use; depending on the materials used to create a formula, how bad a liquid wrench smell varies. The silicon-based liquid wrench is the worst smelling formula and is also the most common.

Working Speed

WD-40 works faster than a liquid wrench. It takes at most 15 minutes to complete its job after application since it is an aerosol.  On the other hand, a Liquid wrench may take hours or even days to work, depending on its state. A liquid wrench in liquid form tends to work fastest, especially when sprayed onto the surface that is to be loosened. Other states like paste take longer to work.


On purchase, WD-40 is more expensive compared to a liquid wrench. The difference comes in because of the materials used in the production of both. WD-40 components are more costly compared to those of liquid wrenches. Also, the cost difference may come in since a single can of WD-40 can serve a range of purposes, while for a liquid wrench, you have to purchase a different formula for each material and purpose.

Final Word

Despite both WD-40 and liquid wrenches being known as penetrating oils, they have numerous differences. These differences range from purpose to constitution. For some purposes like lubrication, they may be used alternatively, but WD-40 serves as a temporary solution. 

Liquid wrench appears in about six formulas that work with different materials and for various purposes. This makes it more versatile compared to WD-40, which makes it a better penetrating oil overall. Some materials like silicon are found in penetrating oils for the same purpose, while others differ for other applications. Despite a few similarities, it is quite clear that WD-40 is not the same as a liquid wrench.

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