If you’ve ever hopped into your car, hit the brakes, and heard a sound that made your stomach drop, you’re not alone. It just happened to Twitch streamer @shagisabadword, who posted about her unexpected trip to the mechanic on TikTok.

“Did you know if you don’t drive your car for long periods of time, it will rust?” She poses the question to her followers. “And it can happen [in] as little as three weeks?”

She let her Kia sit unused for 3 weeks and won a trip to the shop

Here’s the deal: When a car sits unused, especially in damp or humid conditions, surface rust quickly forms on the brake rotors.

Rotors are metal discs exposed to the air. Moisture from rain, dew, or humidity causes oxidation, which appears as rust.

The first time you hit the brakes after the car’s been sitting for a long time, the pads scrape that rust off, making the squeaky or grinding noises that can make any driver nervous.

Not everyone can drive their car regularly

Life happens. Working from home, extended travel, illness, shifts in transportation habits, or owning a second vehicle can influence how long a car sits.

During the pandemic, many people parked their cars for months. Retirees who don’t drive often or folks who store a classic car also face similar challenges. Whatever the reason, letting a car sit without regular use sets the stage for several maintenance headaches beyond rusty brakes.

Brake rust is just the beginning

Tires can develop flat spots where they rest against the pavement. This can lead to vibration and uneven wear when you drive again.

Batteries discharge over time when not charged by regular use, often leading to a no-start situation.

Rubber seals and hoses can dry out, crack, or shrink, leading to leaks or failure of important systems like cooling or fuel delivery.

Fuel left sitting in the tank can degrade, leading to clogged fuel injectors or carburetors.

Fluids like engine oil, coolant, brake fluid, and transmission fluid also benefit from circulation to keep contaminants suspended and systems lubricated.

The mechanic’s advice to the Kia owner to “drive your car more” is more than just a casual suggestion

A 15- to 20-minute drive once a week gets the engine to operating temperature, helping burn off condensation and moisture inside the engine and exhaust system. It lets the brakes scrub off any surface rust and keeps pads and rotors functioning smoothly. Using the car briefly also keeps tires round and suspension components moving freely.

If you can’t drive regularly, at minimum, start the engine once a week 

Let it idle for several minutes to circulate fluids and charge the battery.

Even better, move the vehicle a short distance back and forth to prevent flat spots on tires. 

Parking indoors or under a car cover reduces moisture exposure, slowing rust and protecting paint and trim.

Beyond driving, some other ways to combat brake rust include using a vehicle cover that allows ventilation, applying brake grease or anti-seize on non-friction brake components during servicing, and asking your mechanic to inspect brakes regularly if you know your car will sit for a while.

When I worked in the repair shop, I saw lots of customers worried about noises that turned out to be nothing more than surface rust. Most times, a short drive clears it up. 

Persistent brake noise or vibration, however, always deserves a professional look to rule out worn pads, warped rotors, or other issues.

In the end, your car isn’t a lawn ornament. It’s a machine designed to move. Regular use keeps it healthy, quiet, and reliable. So take that mechanic’s advice seriously: Drive your car more.

MotorBiscuit reached out to @shagisabadword via TikTok direct message for comment. She let MotorBiscuit know that her car is a 2015 Kia Forte LX. The car sat for several weeks because she works from home, and her boyfriend typically drives them in his car. She also added that her mechanic didn’t charge her for the brake inspection.