Grainy Car Paint: 6 Possible Reasons + How To Fix It

There’s nothing more frustrating than getting your car washed only to feel that the surface is rough.

Nothing beats the smooth feeling of a freshly cleaned car, but over time car paint can become grainy. 

Quick Answer

Car paint becomes grainy when there’s a layer of substance overlaying the top coat of paint. Untreated water spots, brake dust, and dust from other things encountered on the road can cause this layer. 

Let’s take a closer look at grainy car paint and how you can get your car feeling smooth again. 

Why Does My Car Paint Feel Grainy?

Quick Answer

Your car paint may feel grainy because of untreated water spots, brake dust, road salt, paint overspray, rail dust, or orange peel. Each of these issues causes your car paint to look and feel rough. 

Car paint may feel grainy due to:

  • Water spots
  • Brake dust
  • Road salt
  • Paint overspray
  • Rail dust
  • Orange peel

Let’s look at these potential problems in more detail:

Water Spots

Water spots can cause a grainy feeling in your car’s top coat of paint if left untreated.

Unfiltered water contains minerals, dirt, and sometimes salt that can make their way into the top coat of paint on your car, causing it to feel grainy and even look different. 

This is especially common when the drops of water are left to dry quickly in the sun.

However, water spots can still happen even without help from the sun.

To help prevent grainy water spots, it’s important to use a microfiber towel to thoroughly dry your car after washing. 

Brake Dust

Sometimes, grainy car paint is caused by the car, itself, rather than an outside factor.

Brake dust, for example, is a common culprit of grainy paint.

This residue is a collection of contaminants that excrete when the brakes are applied, which gets on your wheels and can coat your paint. 

The composition of brake dust can vary depending on the car you drive, as the brake components may differ.

So, this can be a big issue for certain cars and barely an issue for others.

Either way, it’s best to wash your car regularly to prevent brake dust from coating your car paint or mixing with the topcoat. 

Road Salt

During the winter, when the roads get icy, you can expect salt on the roads to melt ice and give cars traction on the road.

Salt can be relatively harmless if washed away within a reasonable amount of time, but it can pose a threat when left on the surface of your car. 

Unwashed road salt can eat away at car paint over time which will leave your car’s surface feeling grainy and even discolored.

Be sure to wash the salt off your car before it gets to this point; if you don’t, it could cause the paint to become grainy. 

Paint Overspray

A common–but rarely noticed–reason for grainy paint is paint overspray.

This is when the paint is sprayed through the air and sticks to the topcoat of your car.

It’s tricky to diagnose because it may not change the overall color of your car, but it can still cause noticeable issues with the topcoat of paint. 

Paint overspray can come from something you are working on nearby, but it isn’t always that simple.

Spray paint can easily travel through the air and make it onto the surface of your car from a good distance away.

This means that the paint may not be yours.

Rather, it may belong to a neighbor painting their house down the street. 

Overspray can make your car paint grainy, but it can also affect other parts of your car.

It can stick to the glass, wheels, and other parts of your car as well, making it difficult to remove completely. 

Rail Dust

Rail dust is another common cause of grainy car paint and can cause issues like rusting.

The main issue is that it’s not as noticeable on non-white cars.

So, you may only notice a rail dust issue because your paint is no longer smooth. 

Rail dust will first appear as tiny orange specs, which you may or may not notice based on the color and cleanliness of your car’s exterior.

Essentially, metal from other sources like railroads or nearby industrial areas attach to your car and eventually begin to rust, which causes the area to turn orange. 

As the metal attaches to your car, you may only notice because of the rough coat on your paint.

Unfortunately, this is still quite common (and unavoidable!) if you live or travel near an industrial area.

I’ll discuss how to correct this issue later, but understand that you can only avoid rail dust by staying out of those areas or with proper treatment techniques. 

Orange Peel

Orange peel is especially common among new cars or freshly painted cars with a grainy or bumpy texture.

Orange peel was so named because the paint looks and feels rough, like the peel of an orange.

Painting issues from the manufacturer for new cars or the company that repainted them cause orange peel. 

Orange peel can happen for many different reasons, but it boils down to a mistake made by the painter of the car.

It’s commonly caused by using too much paint, spraying paint at the wrong angle, or even using the wrong tool to get the job done.

Unfortunately, it’s often human error

There are some techniques you can try to fix orange peel if your car paint feels grainy, which we’ll go over later, but the best way is to have the car sanded and repainted.

You can go to where the job was done originally, or to a more trusted place.

Either way, it’s usually best to let a professional fix the mistake to ensure it doesn’t happen again. 

How Do You Fix Grainy Car Paint?

Quick Answer

Grainy car paint can be fixed by claying, polishing or wheeling, and wet sanding. Certain approaches may be better for fixing grainy car paint depending on how bad the issue is. In severe cases, when none of these solutions are successful, you may need to have the car repainted. 

Remember, not every solution we provide will be the answer to your problem. Your needs may change based on the severity of the issue.

So, let’s talk about these fixes and what will work best for you. 

Clay Your Paint

Using a clay bar to fix your grainy paint is the easiest method available. This is the most commonly used way to resolve issues with your car paint.

It can handle grainy paint caused by water spots, brake dust, and road salt, but it’s a great first step for any texture issues with your car paint, as it can show you how bad the issue is. 

To get started, you need a clay bar, car detailer spray, and a microfiber towel.

The process is simple and doesn’t require any expertise to get the job done.

The best part is that you can check your progress along the way to determine if it’s working.

  • Wash the car. During this process, ensure any and all dirt and grime is gone. 
  • Begin the claying process by spraying. Start with a small area of the car, and spray it with detailer spray. Be sure to use the spray liberally to ensure you get the desired results from the clay bar. 
  • Continue the claying process with your hands. ork the clay in your hands and wipe the clay bar gently across the small surface, going back and forth. Use the towel to clean off any excess detailer spray as needed, and feel free to repeat this process as many times as it takes until the area is smooth. 
  • Continue the process until the paint is smooth. Go over the entire area until your desired results are achieved. 

Make sure to only clay shiny and smooth car paint. If you want to clean matte car paint, there are other ways how to do this.

Polishing (Wheeling) 

Polishing is another way to ensure that your grainy car paint gets back to the smooth feel we all know and love.

Polishing or wheeling, as some refer to it, is the process of heating the car’s paint and allowing it to melt and fill in any rough spots. 

Please note: Polishing is an aggressive option, and you should only attempt this solution if claying the paint didn’t resolve the issue. Furthermore, using this method too often or incorrectly can damage the paint. So, make sure you’re careful with this process and only try it once. 

To do this, you’ll need a polishing wheel and a compound, which allows you to heat the area and melt the paint. 

Before you begin, make sure the car is freshly washed and begin the process of polishing a small area of the car’s exterior.

Verify the pad on the wheel is damp, and apply a good amount of compound to one area of the car.

Apply pressure with the polishing wheel and go back and forth over a surface area to generate enough heat to melt the paint. 

Using the wheel throws the compound and water aside and absorbs some of them into the pad.

Once you notice the water and compound are no longer there, it’s time to let that area dry and move to another part of the exterior.

Be sure to keep your wheel pad clean throughout the process so you don’t spread dirt. 

As you move along, you’ll begin to notice the car’s exterior looking smoother as scratches and rough patches disappear.

Make sure the area you are working on stays wet.

This may require you to add more compound or water as you go. Using a polishing wheel on a dry area can cause the paint to burn rather than melt. 

Car polishing is difficult to do, but has amazing effects and will make your car look super shiny again. If it is to extreme for you, try out other ways to make the car paint look shiny again.

Wet Sanding

Wet sanding uses a lubricant between your car and sandpaper to prevent severe damage from occurring to the exterior of your car.

The most critical challenge of wet sanding is keeping the car’s surface wet throughout the process.

Unlike the previous methods, there’s no such thing as too wet when it comes to wet sanding.

But wet sanding is similar to the above options in that you must start with a clean car.

This ensures the car is wet and that you aren’t sanding dirt and dust into the paint of your car. 

As you begin sanding, there are a few important rules to keep in mind: 

  • Keep water on hand. During this process, it’s a good idea to use a spray bottle for a quick and efficient way to keep the area wet, or just a bottle or bucket of water nearby will work in a pinch. Either way, always ensure water is being applied to the surface of your car generously. 
  • Be gentle. There’s no need to be rough when wet sanding lest you want to ruin the paint on your car. You’re just removing imperfections on the surface of the car, and heavy force is unnecessary and can often be harmful. 
  • Avoid sanding in circular motions. This can lead to overspending areas and makes it harder to recognize when the area needs more water added. So, make sure you are going back and forth in a straight line to get the best possible results when wet sanding.

For some great tips and a detailed overview of this process, check out beginner’s guide video tutorial for how to wet sand and polish paint:

Repainting

The most severe cases of grainy paint may require repainting. Repainting is most likely necessary for issues you can’t fix with the methods listed above. 

Always talk to the company you choose to repaint your car and let them know the details before they start.

For instance, they’ll need to know about grainy surface issues so they can get rid of it before repainting, or you may be stuck with a freshly painted but still grainy car surface. 

Can You Sand Paint To Make It Smooth?

Quick Answer

You can wet sand your car paint to make it smooth, but avoid dry sanding unless you want to repaint the car. Dry sanding gets the job done faster, but it’s rougher on the paint and can potentially cause a lot of damage. Whereas, wet sanding is safer and won’t cause damage.

As long as you are careful and use the correct method, sanding your car can be an effective and cheap way to get the job done. 

Final Thoughts

Whether it’s an outside reason or your car came that way, grainy car paint is an issue that car owners dread. Thankfully, there are ways to fix it.

Try our above methods to get your car feeling smooth again. 

Sources 

Kaliber Auto Detailing: Why Water Spots On Car Paint Is Bad And How To Remove Them

Dr. Beasley’s: What’s The Deal With Orange Peel?

The Drive: How To Clay Bar A Car

Car And Driver: How to Polish Your Car Like A Pro

NAPA Know How Blog: What Is Wet Sanding A Car?

Jan-Lucas Ganssauge
Jan-Lucas Ganssauge