3M Undercoating vs. Chemical Guys Bare Bones Spray – Which Is Better?

3m vs chemical guys - which undercarriage spray is betterWhen you’re looking to fortify the undercarriage of your car against the elements, finding the right treatment can be extremely difficult.

Not all undercarriage treatments are created equal; some may protect against rust but not dirt, whereas others may seal in high quality metal but not necessarily defend it.

In this article, we’ll explain what you need to look for in an undercarriage treatment and why. Then, we’ll compare two of the top undercarriage treatments on the market, the Chemical Guys TVD 104 Bare Bones Undercarriage Spray and the 3M 03584 Professional Grade Rubberized Undercoating so that you’ll know what to look for.

By the time you’re done reading, you’ll be qualified to make a great purchasing decision and protect your car’s most vulnerable area from all that might harm it.

Contender #1
3M 03584 Professional Grade Rubberized Undercoating, Corrosion, Water and Salt Spray Resistant, 16...
Contender #2
Chemical Guys TVD_104 Bare Bones Premium Dark Shine Spray for Undercarriage, Tires and Trim, 1 Gal
3M 03584 Professional Grade Rubberized Undercoating, Corrosion, Water and Salt Spray Resistant, 16...
Chemical Guys TVD_104 Bare Bones Premium Dark Shine Spray for Undercarriage, Tires and Trim, 1 Gal
Contender #1
3M 03584 Professional Grade Rubberized Undercoating, Corrosion, Water and Salt Spray Resistant, 16...
3M 03584 Professional Grade Rubberized Undercoating, Corrosion, Water and Salt Spray Resistant, 16...
Contender #2
Chemical Guys TVD_104 Bare Bones Premium Dark Shine Spray for Undercarriage, Tires and Trim, 1 Gal
Chemical Guys TVD_104 Bare Bones Premium Dark Shine Spray for Undercarriage, Tires and Trim, 1 Gal

What To Look For In An Undercarriage Treatment

Ease Of Application

Ease of application is a critical factor in selecting undercarriage treatments. Some undercarriage treatments can be sprayed on from afar, whereas others must be lathered on with a rag.

Spray-on treatments are not necessarily the easiest to apply, however. When you use a spray on treatment, you will need to protect your eyes, face, and mouth from accidentally coming into contact with the treatment chemical. The treatment chemical may be toxic, so this is not a negligible concern.

In contrast, lathered on undercarriage treatments pose a different set of problems. Rather than worrying about the spray coming into contact with the vulnerable parts of your body, you’ll have to worry about where the excess treatment drips and how to make it reach all of the nooks and crannies of the undercarriage.

Once again, the treatment chemicals may be toxic, so you can’t simply lather them on in your yard if the excess is going to drip into the soil and poison the water supply. Furthermore, lather on treatments can’t be applied when the car is still hot, which introduces an additional barrier.

The 3M undercarriage treatment is a spray. While you won’t need to worry about any dripping of toxic chemicals, you will need to worry about the spray exploding if the can is exposed to extreme heat or pressure – a unique problem aggravated by the flammable nature of the chemical.

It will be much easier to reach into the far crannies of your undercarriage, however. Just remember to put on the right protective equipment before spraying everything down. You should also avoid shaking the spray canister as much as possible.

In comparison, the Chemical Guys undercarriage treatment is liquid, so you will have to lather it on. Watch out for dripping while you lather. If you would rather spray on the Chemical Guys treatment, you can do so with an unpressurized squeegee style sprayer.

This sprayer is much safer than the truly pressurized spraying system on the 3M, which is more akin to a spray paint than a hair dampener. You will be considerably safer if you decide to take this route with the Chemical Guys spray.


The quantity of chemical in the undercarriage treatment matters, especially if you have a vehicle with a large undercarriage like a truck.

The amount you will need to use will also vary depending on treatment. Some treatments require multiple coats before they are truly ready to go, whereas others are one-and-done. It depends on the product, and how frequently the instructions suggest that you use it.

Per unit of volume, spray-on treatments are usually the worse proposition as far as quantity goes. You rarely have to apply more than one coat of a sprayed-on treatment, but because you don’t necessarily have the best control over the amount that leaves the nozzle, you can end up using far more than you need to.

In contrast, lathered-on treatments tend to be a better deal quantity-wise even when they require more than one coat. You can precisely calibrate exactly how much liquid is on your rag so that you don’t waste any to cover the undercarriage of your car.

The 3M spray treatment is no exception to these general rules. While you’ll only need to apply a single coat, the can is pressurized, and you will almost certainly end up using far more than you need when trying to reach far crannies underneath your car.

Unlike with a liquid treatment, a lot of the spray will end up adjacent to the far crannies because you will have to spray it longer to compensate. You will deplete the volume of the spray much faster even though it is much easier to apply to the superficially easy parts of the undercarriage in comparison to the lathers.

In keeping with these principles, the Chemical Guys treatment chemicals offer a lot of quantity per purchase. The liquid, while thin, is easy to apply. You will need more than one coat to provide full protection but applying each coat will be very efficient.

The distant areas of your undercarriage will be just as protected as the ones which are easy to reach. It’s hard to understate the impact that this makes with your consumption of the chemical over time.


The durability of the treatment once applied to your undercarriage is another major concern. Not all treatments last for the same amount of time. Obviously, the conditions in which you are driving your car make a big difference when it comes to the durability of the treatment.

Nonetheless, some treatments are far more durable than others in harsh conditions. The type of harsh conditions matters, too. Extremely hot and sandy conditions might make some treatments degrade much faster than others.

Likewise, cold and slushy conditions with a lot of salt from the road could ablate many treatments faster than warm temperatures would. The tradeoffs here are not always obvious, so be sure to consider the conditions that you drive in the most when thinking about each product.

The 3M spray treatment is superior in cold and slushy conditions, especially with a lot of dirt and salt. This makes it the better treatment for frequent wintertime driving. Furthermore, the 3M treatment can provide better protection against incidental debris which it’s the undercarriage.

Even when the road conditions are extremely harsh, the 3M treatment will provide protection. The catch is that it ablates easily because it is a rubberizing treatment. While contact with snow or slush will not bother the treatment, salt, grime, and debris will chip away at it invisibly and consistently.

The good news is that these contaminants won’t be chipping away at your car itself, but just the treatment. You will need to apply this treatment fairly frequently in harsh conditions if you want its protection to persist.

In very hot weather, the spray lasts a very long time without incident.

In comparison, the Chemical Guys treatment lasts longer in adverse weather conditions but might suffer in the extreme heat. The treatment is a lot thinner than the 3M spray, which means that it is subject to sublimation when in heavy heat.

Freezing cold conditions don’t bother the Chemical Guys treatment. You may need to replace it once every season or so, depending on how much you get into the slush.

Overall, the Chemical Guys treatment is the more durable of the two, with the caveat that it does not always perform better when temperatures are high.

The Verdict

So, how do these two treatment products shape up in the end?

For most purposes, the Chemical Guys treatment is preferable because of its better value, comparable protection, and safer application.

The biggest single difference between the two comes from the fact that the Chemical Guys treatment is lather-on and the 3M is sprayed on. The 3M provides better protection in hot conditions and potentially even in cold conditions, but it just isn’t that durable, and you don’t get much per purchase.

The 3M spray is probably more protective against salted roads and other road chemical hazards.

However you may have a hard time seeing it as a result of the ablation of the treatment itself.

This makes evaluating its efficacy very hard, as you are more likely to find that the spray has been ablated when you try to re-apply it without realizing how much protection the spray offered beforehand.

You will find yourself needing more 3M spray very frequently, and you’ll also find that applying it is inefficient and often a hassle. Especially if you don’t have the necessary protective equipment before making the purchase, the 3M spray’s benefits simply are not worth its drawbacks.

Now that you know the winner of the two undercarriage treatments, it’s time to go forth and treat your undercarriage the right way.

Remember to think about the conditions that you drive in the most frequently, how much you’ll tolerate difficult application, and how frequently you would prefer to replace your chemical treatment. Stick to following the instructions that the treatment’s manufacturer specifies for the best results.

Brett Gordon

The engine behind editing at DigMyRide and the brains behind its build. During the day, Brett is a thirty-something dude from SoCal climbing the corporate ladder, but by night, he spends his time contributing to the online world of automotive tech & trends.