I Face Loud Transmission Noise on Kia Stonic 2020 During Long Drives

I own a Kia Stonic 2020 1.4 MPI Elegance Design, and I am experiencing a serious issue with the transmission. Whenever I drive the car for a longer distance, a loud whining noise starts coming from the transmission. I have taken my car to several authorized service centers, but each one has given me a different explanation. Some acknowledge the issue but say they cannot find a solution, while others claim that there is no detectable problem at all.

As time goes by, the situation has worsened. The gear shifts have become rough and noticeable, and the transmission seems confused during operation. The noise has grown louder, making me anxious that the car might break down on the road at any moment. According to one service, the problem occurs because the transmission oil overheats during longer drives, causing the gears to wear out. However, instead of fixing it, they just refer me to Çelik Motor, where I am told to wait for a follow-up—yet no real action is taken.

This ongoing problem has caused me both financial concern and emotional distress. I fear that the transmission may fail completely if not addressed soon. I demand that Kia and Çelik Motor provide a permanent solution to this issue, including repairing or replacing the faulty transmission components under warranty. I also expect a clear explanation of the root cause and an apology for the inconvenience. Please resolve this matter urgently before it leads to greater safety risks.