Using a brush at a self-service car wash can indeed scratch your car. Here are some key points based on various sources:

1. Scratching and Swirl Marks: Many users and experts agree that brushes, especially those made of stiff bristles, can leave scratches and swirl marks on your car's paint. This is particularly true for darker-colored vehicles, where scratches are more visible.

2. Recommendations Against Brushes: It is widely recommended to avoid using the brushes provided at self-service car washes. Instead, using a microfiber cloth or a foam cannon is suggested to minimize the risk of scratching.

3. User Experiences: Many car owners have reported negative experiences after using these brushes, stating that they ended up with scratches on their vehicles.

4. Alternative Washing Methods: If you want to wash your car at a self-service station, consider bringing your own wash mitt or sponge to avoid using the provided brushes. This can help protect your car's finish.

Visual References

Here are some images related to self-service car washes and brushes:

In summary, it's best to avoid using brushes at self-service car washes to protect your vehicle's paint from scratches and damage.