The most exposed and least protected side of any vehicle is its underside. Despite housing some pretty important systems and components, the undercarriage, as it's also called doesn't come protected from the road and what it throws at. While some do, most car manufacturers just seem to completely forget the underbody when it comes to protecting it from flying debris, sharp objects and salt.
While today's cars are much better at surviving extremely corrosive conditions they are still not as good when it comes to living near the coast. Hence why most people tend to take matters into their own hands.
Benefits of Underbody Paint
Protection
Also known as undercoating, underbody paint is used to protect the various components exposed to road grime. This comes in the form of rust protection as well as protection from stone chips and mud. The same is used on the wheel well and it's also used as protective wheel arch paint since the arches are also exposed to the same hazards.
Longevity
By being able to protect the underside of your vehicle you're not only keeping it's floor in good shape for a lot longer but you also increase the chances of prolonging the lifespan of certain components. This includes both suspension and exhaust parts.
Cleaning
With textured car paint under your vehicle, you are able to keep the underside much cleaner. You might ask – who cleans the undercarriage? But when you have lots of salt being deposited on the road or unpaved roads, you might as well dip your car in a big bubble bath. With a TXT coating, you won't need to worry about water sticking about when you use a pressure washer.
How to Apply Underbody Paint on the Wheel Arches
Preparation
1. The key to this process to be successful is good preparation. This means having the right tools as well as prepping your car the right way. First off you'll need tools such as a grinder, sandpaper, a jack, jack stands, a paintbrush, a towel, a degreaser agent and the wheel arch paint.
2. The second part of the preparation process is to lift your vehicle up and set it on jack stands. The wheels should also come off to make applying the protective coating much easier. You should then proceed by taking care of some surface rust if present. Otherwise, go straight onto the application process. Use a piece of sandpaper if the level of surface rust on the arches is minimal, otherwise revert to using a metal bristle brush.
Application
1. After getting your car in the air and getting rid of any rust, clean the wheel arches and the wheel well using the degreaser agent, the best here is to use WD-40 but whatever you have at hand is going to work just fine.
2. When applying the TXT coating on the wheel arches and wheel well make sure to cover every bit of surface. It's also important that you apply the coating evenly and have multiple layers on top of each other. Let the coating dry for about an hour and then apply another layer.
Types of Coatings You Can Add
Wax-Based
The most affordable and easiest to apply textured car paint to your wheel arches and undercarriage is a wax-based or paraffin coating. This comes in the form of liquid and it's able to fill even the smallest of crevices and dents. But as you'd expect it all sounds too good to be true and it is since a wax-based coating is not durable. You'll need to apply it every year or every other year depending on the area you live in.
Rubberised
With a rubberised coating, you can expect any stone chips to bounce off of it since it's actually made of rubber. Although this is a softer coating than a wax-based one it's quite protective. One downside with a rubberised coating is that it doesn't fill up everything however it's easy to apply. If combined with a wax-based coating it can be a winning combination.
Polyurethane
With a polyurethane coating, you can expect to spend the most amount of time applying it as it has quite a specific process. Unlike a rubberised coating, it fills up every little nook and cranny while it also pushes out salt and moisture. At the same time, you won't get a scratch-free underside you definitely won't need to use two different coatings to protect it well.
Final Thoughts
No textured car paint is perfect but it's a lot better having it on your vehicle than not. As you already know it can be detrimental to leave the undercarriage unprotected. If you want to keep your car around longer than the warranty the dealership gave you, make sure to coat the underside especially the wheel arches in a protective solution.