Iconic and extremely versatile corrosion-inhibiting spray. Every toolbox should have some
WD40 Multi Use
7 10

WD40 Multi Use 420ml is the ubiquitous and iconic maintenance spray that takes its name from the 40 attempts its inventor made to perfect the formula.

Old as the hills, it remains a godsend for everyday jobs such as freeing sticky control cables, driving moisture from electrical contacts or just keeping pesky squirrels off garden hardware (no joke - here's a video).

Just like Coca Cola, WD40 was never fully patented, which allows them to keep the exact formula under wraps. What I can tell you is that it's derived from petroleum distillates that disperse water, gobble gunge n' grime, while leaving behind a thin, protective lubricant film.

This explains how it cures squeaks and keeps chrome looking spotless, but shouldn't be used as an everyday chain lube. But harness its charms to good effect on stubborn fasteners and seatposts and stems on the cusp. But properly seized compenents need the brands' new fast release penetrative spray, which I will review separately.

One of my most surprising WD40 triumphs was a cheap but cheerful rear blinky light with a faulty seal. This had allowed water inside, partially corroding the switch. Removing the back and directing two-second blasts at close range to the affected area while simultaneously toggling its rubberised switch fixed this - good as new in ninety seconds.

Handle with some care though; WD40 will soften car polishes and similar products on contact (placing strips of cardboard beneath bare cable runs before giving them a quick hit solves this) and its highly invasive nature means you'll need to take extra care around rubberised synthetics and even unsealed bearings.


Iconic and extremely versatile corrosion-inhibiting spray. Every toolbox should have some.

road.cc test report

Make and model: WD40 Multi Use

Size tested: n/a

Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?

"WD-40 lubricates moving parts such as hinges, wheels, rollers, chains, and gears. It protects against rust and corrosion on items like tools, and sporting equipment. It penetrates to free stuck corroded parts like nuts, bolts, valves and locks. It quickly removes adhesives, corrosion and paint. It displaces moisture to restore water flooded equipment such as engines, spark plugs and power tools."

Does exactly what it says on the tin.

Tell us some more about the technical aspects of the product?

Operating Temperature: -10˚ F to 200˚ F

Dielectric Strength: 44,400 - 47,800 Volts

Solubility in Water: Insoluble

Surface Compatibility

For all variations : WD-40 demonstrates none to negligible deleterious effect to plastic, rubber, and metal hard surfaces. This includes Acetal, neoprene/hard rubber, HDPE, PPS Copolymer Polysulfone, Teflon, Viton, steel, galvanized steel, hot dip, electroplated, copper, brass, magnesium, nickel, tin plate, titanium, and zinc.

Performance - WD-40® Multi-Use Product

Surface Cautions

Nearly all surfaces interact with WD-40 as they would any high grade aliphatic petroleum spirit. Certain types of rubber will swell upon prolonged immersion. Wax polishes and certain wax coatings may be softened by WD-40. Clear polycarbonate and polystyrene may stress craze or crack. Always test surfaces first.


17 um (US)

600-1000 ft2 per gal


Lubricates and Protects

Extreme Pressure Lubrication

Corrosion Protection (Salt Spray)


0.60-0.70 mm at RT

1300-2000 lbs

0-20% in 72 hours

Rate the product for quality of construction:
Rate the product for performance:
Rate the product for durability:
Rate the product for weight, if applicable:
Rate the product for comfort, if applicable:
Rate the product for value:

Tell us how the product performed overall when used for its designed purpose

Something of an institution, WD40 is an extremely versatile generic spray that does exactly what it says on the tin. However, I'd urge caution around certain materials - rubberised plastics, seals, suspension components etc.

Tell us what you particularly liked about the product

Versatile and extremely effective.

Tell us what you particularly disliked about the product

Can be a little too invasive sometimes.

Did you enjoy using the product? Yes.

Would you consider buying the product? A workshop staple.

Would you recommend the product to a friend? Yes.

Overall rating: 7/10

About the tester

Age: 38  Height: 1m 81  Weight: 70 kilos

I usually ride: Rough Stuff Tourer Based around 4130 Univega mtb Frameset  My best bike is: 1955 Holdsworth Road Path and several others including cross & traditional road

I've been riding for: Over 20 years  I ride: Most days  I would class myself as: Experienced

I regularly do the following types of riding: cyclo cross, commuting, touring, fixed/singlespeed, mtb,


Shaun Audane is a freelance writer/product tester with over twenty-eight years riding experience, the last twelve (120,000 miles) spent putting bikes and kit through their paces for a variety of publications. Previous generations of his family worked at manufacturing's sharp end, thus Shaun can weld, has a sound understanding of frame building practice and a preference for steel or titanium framesets.
Citing Richard Ballantine and an Au pair as his earliest cycling influences, he is presently writing a cycling book with particular focus upon women, families and disabled audiences (Having been a registered care manager and coached children at Herne Hill Velodrome in earlier careers)


Angelfishsolo [130 posts] 3 years ago

Shame it strips oil and grease away and shortens the life of the bikes drive chain.  2

fennesz [124 posts] 3 years ago

Can you review GT-85? Smells nicer, for sure...

Nick T [912 posts] 3 years ago

That end of summer slump for new kit releases to review is really hitting hard eh.

Dave Atkinson [6083 posts] 3 years ago
Nick T wrote:

That end of summer slump for new kit releases to review is really hitting hard eh.

WD40 sent us their full range of new bike-specific products to have a go on. but since we hadn't actually reviewed WD40 itself, we thought we'd bung it up first.

look out for the other WD40 products soon...

RhysW [81 posts] 3 years ago
fennesz wrote:

Can you review GT-85? Smells nicer, for sure...

I would go for the US Break Free - brilliant stuff! Knocks the socks off even GT for smell!

RhysW [81 posts] 3 years ago

Maybe worth checking with WD-40 is the product is corrosive to synthetic rubbers and paints - very possibly this is an old wives tale if used sensibly.

Shaun Audane [137 posts] 3 years ago

WD40 isn't corrosive to paintwork. However, the solvent properties can dissolve, or at least soften polymer waxes. Similarly, there are so many different kinds/compositions of rubberised components-hence a note of caution.