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Best Undercoating Spray of 2020: Rust Proof Your Car or Truck

The worst thing about vehicle maintenance is that it’s so incredibly pricey. It can quickly drain your budget before you even realize it.

Undercoating, in particular, is extremely expensive. Not only do you have to pay a lot, but you also have to wait (at least) a couple of days to get the job done. It doesn’t have to be that painful, though.

You can do everything on your own by getting an appropriate undercoating solution. You can also get your hands dirty without having to spend a fortune.

The Best Undercoating Spray

3M Undercoating
16 oz
Fluid Film Undercoating
128 oz
CRC Industries Undercoating
CRC Industries
16 oz

1. 3M Professional Grade Rubberized Undercoating

The first entry on the list is an outstanding undercoating spray that comes from 3M. The spray comes with a very affordable price, but it can offer so much more than the basic undercoating sprays.

Namely, this spray can be used not only on cars but on vans, trucks, and even RVs as well. So, it’s as universal as it can be. On top of that, the spray can effectively remove any traces of rust and it’s equally great against both corrosion and abrasion too. You can also apply the coating to protect floor pans, wheel wells, trunk lids, and even the interior side of fenders.

One of the main issues with a vehicle’s undercarriage is that, as time goes by, it gets noisier and noisier. At one point, the noise will be unbearable. This spray can minimize the noise very effectively as it provides outstanding insulation for your vehicle’s cabin. If you decide to use this spray for your vehicle, you can rest assured that you will no longer have to deal with those annoying and distracting sounds.

If you care about your undercarriage and if you want a cost-effective solution to protect it properly in the long run, you should absolutely give this spray a chance.

2. Fluid Film Underbody Protection

The second undercoating solution on the list is not as universal as the previous one but you can be sure that it does its job perfectly. This can of spray is all you need to ensure that your undercarriage is well protected in the long run.

This undercoating solution not only stops the rust from further accumulation, but it also prevents it as well. On top of that, the protection is very durable and solvent-free. As long as you apply it on a regular basis, you can rest assured that rust will no longer be an issue for your vehicle. Also, you can use it just as effectively for both cars and trucks as well.

The best thing about this undercoating protection is that it’s completely eco-friendly and it uses only natural ingredients (such as lanolin). Other than that, this undercoating solution also has an antifreeze agent. So, winter will no longer be one of your foes either.

There is one particular downside that has to be noted here. Even though this undercoating solution is advertised as “multi-purpose” protection, the truth is, it’s far from that. Even though it’s very effective against both corrosion and abrasion, the protection is still not on the same level as anti-rust protection. It’s not a major flaw as it still does its job well. But, if you want consistent quality, you will probably have an issue with this.

3. CRC Rubberized Undercoating Spray

Here’s another great undercoating spray that is very simple in theory and very effective in practice. If you’re looking for a low-cost solution that will keep your undercarriage properly maintained, this is the product for you.

CRC 05347 can provide very flexible protection against salt, moisture and other types of rust. It’s very easy to use and it has a low VOC formula. That means that you can quickly notice the effects and the spray will also dry fairly quickly. You can apply this undercoating solution to decks, frames, fenders, doors, and even panels as well. Along with that, this spray is also soundproof, which means that it insulates your vehicle cabin from the outdoor noise. It works like a charm!

The spray is very durable as well and, once you get it, you can be sure that you’ve got a long-term solution. On top of that, you don’t need to apply a lot of it to protect your vehicle. Even the minimal amounts are enough to keep your undercarriage in good shape.

If you’re low on money but you need a reliable undercoating solution, give this spray a try. You will not regret it.

4. PlastiKote Rubberized Undercoating

PlasiKote’s 272 is a great way to protect your undercarriage from heat, dust, fumes, moisture, rust, corrosion, and even the cold itself. In short, you are properly covered everywhere. The spray is easy to use and it’s very durable. You can expect one spray to last for at least six months (if you use it properly, of course). The materials are 100% eco-friendly and, unlike many similar sprays, there is no asbestos fiber whatsoever.

The outdoor noise can be very distracting even if you’re driving short distances, but with this spray, that will no longer be an issue. This undercoating spray provides sufficient soundproof protection and it ensures that any noise that is coming from the outside is at the lowest level.

This undercoating protection can be classified as a “budget-buy” product and you should absolutely give it a go. You will hardly find a better offer for a similar price.

5. RUSFRE Spray-On Undercoating

While the last entry on the list may not be as flexible as the previously mentioned undercoating sprays, you can rest assured that the quality is on a very high level.

The chemical formula contains bound fibers that will prevent cracking, peeling, and chipping of your undercarriage. It also contains rust inhibitors that can be used to prevent the rust from being accumulated in the first place. At the same time, this chemical formula will effectively minimize any noise that comes from the quarter panels, wheel wells, fenders, and the undercarriage itself. You can apply the coating very easily and you can use it on pretty much any surface. Of course, as long as the surface is properly exposed.

This undercoating solution is a bit pricey, but it’s well worth the money. The capacity is great and one can of spray will last at least six months. You will actually save some money along the way as, unlike some other similar products, you will be perfectly fine even with just a single can.

Good quality is never cheap and if you want a reliable long-term undercoating solution, this is the product for you.

Styles of Undercoating

undercoating spray

Typically there are three types of undercoat; spray, rubberized, and paint applications. Most of the options we list were sprays.

An undercoating spray is usually the easiest application of the bunch. Spray applications seal away the road and prevent chemicals and abrasive material from harming the underbody.

Rubberized undercoating protects your underbody from moisture and corrosion. When looking for an undercoating, rubberized options usually offer the best results. They seal better and protect from moisture quite well.

Paint options help prevent rust and they are also readily available in large quantities. Usually, this option is the more budget-friendly option. Paints will dry faster than the other two options, but obviously, have their drawbacks in comparison to effectiveness.

How to Apply an Undercoating

It is possible to pay someone to apply an undercoating to your vehicle. You can also save some money by doing it yourself. Before you start, ensure you have the listed products and the space available to accommodate your vehicle.

1. Use a pressure washer to remove dirt, mud, dust, and any other debris from the underbody.
2. Use a degreaser to clean the underside of your vehicle.
3. Find any rust and remove it with a grinder.
4. Any remaining rust can be removed with 220 grit sandpaper.
5. Use paint and primer on the underside of the vehicle. Allow these to dry before moving on.
6. Apply the undercoating to the underbody of the vehicle. Do so liberally and cover any parts that are exposed to the road.
7. Once dry, apply a second coat.

If you ever need to remove your undercoat, apply an undercoating removal spray and allow the undercoat to soften. Once it’s soft enough use a scraper to remove it.


All of these undercoating options have their pros and cons. On the other hand, all of them provide a rust proof solution and all of them are viable choices. Regardless of which of these undercoating options you are planning to buy, you can rest assured that all of them will protect your undercarriage well. At the same time, all of them provide an exceptional value for the given price. As a buyer, that’s exactly what you should look for.


Richard Reed
I've been a General Manager of a moving company and I've also been a Professional Mover for over 30 years. I've driven flat beds, reefers, dropdecks, moving vans, heavy machinery, etc. In my time as a Mover I've driven over 1,000,000 safe miles. My days of moving and driving truck are past me but The Vehicle Lab allows me to share the knowledge I've gained over the past 40 years.

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