WD40 is a popular multi-use product that claims to penetrate stuck parts, displace moisture and lubricate almost anything. With its supposed ability to loosen rusty bolts and free stuck mechanisms, it’s no wonder many car owners wonder if WD40 can be used to remove rust from brake components.
Rust on brakes is a common problem, especially for vehicles in cold winter climates where roads are salted or coastal areas with exposure to ocean air. Brake rust can lead to seized caliper pins, slider pins and pistons as well as rotor rust and corrosion. But is WD40 an effective and safe way to remove this troublesome brake rust?
Page Contents
Can WD40 Remove Brake Rust?
The short answer is no, WD40 should not be used to remove rust from brake parts. While WD40 can penetrate rust and provide temporary lubrication, it does not fully remove rust or stop it from returning. More importantly, there are safety concerns with using WD40 on brakes.
WD40 Only Temporarily Penetrates Rust
One of the main claims of WD40 is that it can loosen rusted parts by penetrating the rust. When sprayed on rusty brake components like caliper pins and pistons, WD40 can work its way under the rust to provide some temporary lubrication. However, it does not fully remove the rust or stop it from returning.
WD40 works by displacing water and providing a light oil lubricant. While this may free up stuck brake parts, it does not remove the rust that has formed. The rust is still present and will likely return quickly, especially if the brakes get wet again. So while WD40 may provide short-term improvement, the rust will be back necessitating proper removal and prevention.
Safety Concerns Using WD40 on Brakes
More importantly than its limited effectiveness at removing rust, using WD40 on brake parts raises major safety concerns:
- WD40 can contaminate brake pads – Any WD40 that gets on the brake pads will contaminate them, greatly reducing braking performance. Contaminated pads need replacement.
- WD40 leaves an oily film – The light oil left behind by WD40 can interfere with proper brake operation and leave brakes slippery.
- Risk of catching fire – The petroleum distillates in WD40 are flammable. Spraying them near hot brakes or the exhaust is extremely dangerous.
For these reasons, automotive experts strongly advise against using WD40 to remove rust from brake components. The risks far outweigh any temporary benefits.
Effective and Safe Ways to Remove Brake Rust
While WD40 is not recommended, there are several effective and safe ways to remove troublesome brake rust:
Mechanic Cleaning
The best way to thoroughly remove brake rust and rescale components is to have a professional mechanic do it. They have specialized tools and cleaners designed specifically for brake cleaning and de-rusting. Mechanics can fully clean caliper pins, slider pins, pistons and other components and then lubricate them properly for smooth operation. This addresses the root cause – the rust.
Brake Cleaner Spray
Specialized brake cleaner sprays are formulated to rapidly penetrate and dissolve brake dust, oil and rust buildup. Products like CRC Brakleen work well to break down rust on calipers, rotors and brake hardware. Ensure cleaners are completely rinsed off brake parts with water after use.
Vinegar Soak
As a home remedy, rusty brake parts can be soaked in undiluted white vinegar to dissolve rust. After soaking 1-2 hours, scrub with a stiff brush and rinse well with water. Vinegar is safe for brake components if thoroughly rinsed.
Sanding/Resurfacing Rotors
Heavily rusted rotors can be sanded down to expose fresh metal beneath. This removes the rust and resurfaces the rotors. Use 80-120 grit sandpaper and be cautious not to overheat rotors while sanding. Rotors must be replaced if too thin.
Rust Preventatives
Once brakes are cleaned of rust, apply rust preventing sprays or lubricants to protect components from future corrosion. Products like CRC Marine Rust Inhibitor or white lithium grease can help keep rust at bay.
Conclusion
In summary, WD40 is not an effective or safe solution for removing rust from brake parts. While it can temporarily penetrate rust, it does not fully remove it and poses contamination and fire risks. Professional mechanic cleaning, brake cleaner sprays, vinegar soaks and sanding rotors are smarter ways to eliminate brake rust without compromising safety. Be sure to apply rust preventatives after cleaning to keep the corrosion away. With the right methods, you can keep those brake parts rust-free and performing smoothly.
Frequently Asked Questions
Why does my brake rust so quickly?
Brakes rust quickly due to exposure to water, road salt and humidity. as brake pads wear down, the caliper and rotor are increasingly exposed to the elements. Coastal climates and cold winter areas with salted roads see accelerated rusting. Stagnant water sticking to components causes flash rusting.
What problems can brake rust cause?
Rust on brake rotors causes poor stopping power and an annoying pulse in the brake pedal. On caliper components, rust can seize pins, pistons and springs leading to stuck brakes. Excessive rust requires replacement of parts.
How do I prevent brake rust?
Regularly lubricating caliper pins with silicone paste keeps moisture out. Spray rotors with rubberized undercoating for winter. Store vehicle out of the elements when possible. Apply rust inhibitor sprays to all undercarriage components including brakes.
Can I just sand rust off my brake rotors?
Yes, using 80-120 grit sandpaper to remove rotor surface rust is effective. Completely remove rust down to bare metal. Resurface evenly avoiding grooves. Replace rotors if too thin – minimum thickness is typically stamped on rotors.
Is brake cleaner better than WD40 for rust?
Definitely. Specialized brake cleaners like CRC Brakleen quickly penetrate and dissolve rust on brake parts. WD40 does not fully remove rust and leaves an oily film. Brake cleaner is formulated specifically for brakes.
Key Takeaways
- WD40 only temporarily penetrates rust but does not remove it from brake components.
- Using WD40 on brakes poses risks of contamination, losing braking ability and fire.
- Have a professional mechanic properly clean brakes to remove rust and prevent future corrosion.
- Brake cleaner sprays and vinegar soaks can dissolve rust if done properly.
- Prevent rust by lubricating and protecting components from moisture.