Best Rust Prevention Spray for Cars: Boost Your Car’s Lifespan
Give your car the rustproofing and protection it needs.
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BY Norah Tarichia / LAST UPDATED ON April 12, 2021
Most scratches, minor dents, peeling, or flaking paintwork are minor flaws that you can correct without using many tools. However, there’s nothing more tedious than removing heavy scaly rust from your vehicle. You may need to use a combination of heavy-duty sanding tools and rust-removing agents to restore the look of your vehicle—that is if the rust hasn’t done so much damage that you need to replace the part. The best way around this is that you shouldn’t leave it until it’s too late. Even before you start seeing signs of rust, treat your vehicle with a rust-prevention formula. You can conveniently do so with a rust prevention spray, where with just a few spritzes, you will create a sealed finish that blocks moisture and prevents oxidation. What’s more, most of these formulations also act as rust removers or converters. So if you’re looking to keep your car in tip-top condition, this guide is a great starting point.
This formulation doubles as a rust inhibitor and a waterproof lubricant and is safe for any metal, plastic, or vinyl surfaces. It comes in a 12-ounce bottle.
- Effectively penetrates moving parts for lubrication
- Leaves a thin waxy film for prolonged protection
- Loosens rust and flushes out old lubricants
- Safe for bicycles, marine, and automotive equipment
- Leaves a messy finish that needs to be rubbed in for a neat appearance
This oil-based formulation comes in a 10.25-ounce bottle and works by loosening rust and preventing further corrosion. It takes about 20 to 40 minutes to dry.
- Affordable solution for eliminating rust on any metal surface
- Doesn’t chip or flake once it’s fully cured
- Converts a rusty surface to a paintable surface
- Spray can is fitted with an any-angle-spray that can be sprayed in any direction
- Nozzle opening may clog up with time
- You may need more than one bottle to cover your vehicle's exterior surfaces
Coming in a 12-pack, this spray-on rust treatment dissolves rust within minutes and leaves behind a protective primer to keep rust from forming.
- Application is very easy—simply spray it or brush it
- Can be used on all automotive parts
- Leaves behind a long-lasting coat that can be painted over
- Dries within minutes when sprayed in small patches
- Has an overpowering smell
- You need to apply another primer over it before painting to prevent blistering
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Benefits of Rust Prevention Spray
- Saves money. Rust can cause serious problems with your vehicle, and treating accumulated rust is an expensive venture. Rust-proof spray for cars ensures you tackle the problem before it becomes a big financial drain.
- Maintains the resale value. Rust damages your car, lowering its value. If you protect your car against rust, you may get a better offer because it looks good and runs smoothly.
- Improves durability. Cars eventually wear down over time. Keeping yours rust-free is one way to make sure it gives you great service for a long time.
- Reduces accident possibilities. Anti-corrosion spray for cars ensures that all parts of your car are well-maintained and functioning properly. If every component works as it should, chances of mechanical failure and accidents are minimized.
Types of Rust Prevention Sprays
Inhibitors are specially designed to prevent rust on surfaces. They slow down the process of oxidation, which leads to rust. They should be used before rust appears, and the best rust inhibitors for cars are a great preventive measure, especially in humid areas.
Removers are considered some of the best rust-proofing sprays for cars. This is because, unlike inhibitors, you can spray them directly on rust. They bond with rust, and the resulting substance can be washed off with soap and water. You can also use removers as inhibitors.
Primers form a base, which is a treated surface you can paint over. They are usually combined with removers to create powerful rust prevention sprays. Primers are bonding agents that create a bond between the surface beneath them and the paint applied on top. Their main job is to make the paint stick well to the surfaces.
3M was founded in 1902 as Minnesota Mining and Manufacturing Company. The discovery of a low-grade mineral transformed the company into a global innovator with brands and products in more than 10 key industries. Today, it is a hugely successful company known for products such as Professional-Grade Rubberized Undercoating
Founded by Robert Fergusson in 1921, Rust-Oleum has a track record of manufacturing some of the best protective paints and coatings for home, automotive, and industrial use. It’s a subsidiary brand of RPM International Inc. and is headquartered in Vernon Hills, Ill. One of its best-selling rust converter and prevention spray is the Rust Reformer Spray.
VHT Paints is a subdivision of Dupli-Color, which has been manufacturing automotive care products since 1938. VHT stands for Very High Temperature, which is a reflection of what its products are designed for. It’s a manufacturer of automotive paints, rust treatments, and coating systems that can withstand being used in high-heat applications.
Since 1909, Permatex has been at the forefront of the automotive industry. It produces car products for both residential and commercial use. It’s a trusted brand with a presence in over 80 countries. One of its best-selling products is the Rust Dissolver Gel.
Rust Prevention Spray Pricing
- $5-$10: If you are on a tight budget, this is a great place to start. A spray in this price range works as a rust converter for any metal surface.
- $11-$20: There are more options in this price range. Sprays come in 12- to 16-ounce cans and leave a clean finish.
- $20 and up: Some of the best undercarriage rust protection products come in at this price point. Most rust preventers that cost over $20 can be painted over. Some manufacturers sell two or three sprays in a pack, so you get great value for your money.
A rust prevention spray must have corrosion inhibitors to help protect your vehicle from the effect of daily wear that comes with living in a humid environment. Ideally, it should leave a long-lasting protective film that keeps out moisture and prevents oxidation to preserve the quality of the metal.
The drying time separates the best rust stoppers for cars from the worst. You need a treatment that takes only a few hours to settle and dry. This is important if you are considering painting over the area. If the spray takes too long to dry, you may have to wait for hours — or days — before painting your car.
- Quantity. You need to consider how large the surface is so you can decide if one bottle is enough. For example, to treat large surfaces such as the car hood or the doors, you may need more than one bottle to get the job done.
- Color. Some formulations may leave behind a black matte finish when they dry, while others may leave a transparent film. The former can help you easily identify the areas that have been left untreated. However, if you intend to paint over the surface, prioritize sprays that leave a transparent layer.
- Type of Surface. You need to consider the type of surface the formulation is designed for so you don’t end up corroding it. For example, some formulations are only suitable on metal and may corrode fiberglass, vinyl, or plastics. However, you can find multi-purpose formulations that can be used to treat rust on any surface.
Best Rust Prevention Sprays Reviews & Recommendations 2021
- When using rust inhibitors, it is vital to know which ones require prior preparation of the rusty parts. Not all sprays can be used directly on rust. Some work as preventers while others work as treatments.
- Be sure to check whether your rust prevention spray can be used with paint. Although the sprays leave a clean finish, painting over the surface afterward might be ineffective. Also, confirm whether it's safe for bodywork.
- Always wear the right gear. Rust preventers for cars can have a strong odor that may overwhelm you. A pair of gloves and a nose cover may be very useful.
- Make sure you get extra cans. This will ensure you cover every part, and you can store any additional products for future applications.
- If you aren’t sure of the effect, test the spray on a small area first.
- Depending on the car part, you can choose the most effective application method. Spraying is the top technique, as the formula gets to all the nooks and crannies. However, there are situations when you may need to consider applying the formula using a cloth.
Q: Which is the best rust prevention product?
While all the rust prevention sprays featured on our review are some of the best on the market, we rate BOESHIELD T-9 Rust & Corrosion Inhibitor highly for its high-grade rust prevention, anti-corrosion, and lubricative properties.
Q: Can these rust removers be used on household products?
Anti-corrosion sprays for cars have harsh chemicals that might not be suitable for food-grade household items. You can use products such as Evapo-Rust Super Safe Rust Remover to clean household items. DIY home remedies for rust removal — such as vinegar, baking soda, and acetic acid — also work well.
Q: What’s the difference between rustproofing and undercoating?
Rustproofing involves applying a rust inhibitor on any surface of the vehicle that may be prone to rust. In contrast, undercoating involves applying a sealant coat on your car’s undercarriage to protect it from rust, corrosion, or minor scratches.
Q: What is a rust inhibitor?
A rust inhibitor or a rust stopper is a chemical that slows down the oxidation process that causes rust. It seals the surface with a long-lasting coating that locks out moisture and oxygen, both of which are necessary for rust formation.
Q: Can rust inhibitors be applied to areas that get hot, such as exhaust pipes?
Unless stated otherwise, manufacturers do not advise applying these sprays on areas that exceed 200 degrees Fahrenheit (93 degrees Celsius).
We found the BOESHIELD T-9 Rust & Corrosion Inhibitor to be the best rust prevention spray for most vehicles. It utilizes anti-corrosion and waterproofing technology to provide effective rust protection. If you only need a budget-friendly rust remover to remove small traces of rust on your vehicle’s body, then you can use the Rust-Oleum Rust Reformer Spray.