What is the reason for the squeaking sound when reversing but not when moving forward?

[VonVanessa]

The reason for the squeaking sound when reversing but not when moving forward is due to foreign objects between the vehicle's brake caliper and brake disc. Precautions for reversing include: 1. Before reversing, check the situation behind the vehicle, predict the reversing route, and determine whether the front of the vehicle will hit obstacles during the reversing process; 2. When the steering wheel is turned significantly, the turning radius of the vehicle's steering wheels is larger than that of the rear wheels, and the front of the vehicle swings outward more during reversing, so be careful to avoid scraping the front; 3. When the rear of the vehicle moves to the right rear, turn the steering wheel to the right, and vice versa, turn it to the left, which is consistent with the steering operation when the vehicle moves forward.

[VanCaleb]

As someone who has driven quite a few cars, I've encountered this kind of squealing sound when reversing, but it's completely silent when moving forward. This usually occurs in the braking system or suspension components. The most common issue is between the brake pads and rotors - when reversing, due to the car's backward inertia, the brake pads may rub against the rotors and produce abnormal noises. When moving forward, the force direction is different, so there's no sound. Secondly, worn bearings or ball joints in the suspension system can also cause deformation under force when reversing, resulting in noise. I once experienced loose wheel bolts where the tire would slightly wobble and make noise when reversing. This isn't a minor issue - it can gradually deteriorate braking performance or lead to safety accidents. I suggest doing a quick visual check of the wheels and chassis for any loose components first, then take the car to a professional shop for comprehensive equipment inspection as soon as possible. Don't delay - last month I nearly had an accident in a parking lot because I ignored this. Remind mechanics to check these areas during regular maintenance to prevent problems in advance.

[ParkerRose]

I remember encountering this weird buzzing sound when I was learning to drive. It was particularly alarming when reversing, but completely silent when moving forward, which really raised safety concerns for me. From what I understand, the issue likely lies in components underneath the car, such as the rear axle bearing or driveshaft area. When reversing, the wheels and drivetrain experience reversed stress directions, potentially causing increased friction noise. During forward motion with steady load, everything stays quiet. Another possibility could be a faulty brake pad return spring, which only reveals the problem during reverse. When hearing such sounds, I first stop the car and test reversing a short distance on level ground to confirm if it only occurs in reverse. Then I check around the tires for any foreign objects or looseness. If the sound persists, I absolutely don't force driving and immediately head to a repair shop for inspection, as it might indicate suspension damage or wheel misalignment - losing control during nighttime reversing would be disastrous. For maintenance, I have these vulnerable components professionally checked every six months to ensure daily driving safety.

[LaCora]

When tinkering with car modifications, I often research abnormal noise issues. If there's a squealing sound in reverse but no issue when moving forward, 90% of the time it's related to the driveshaft or differential. Reverse operation changes the torque direction, and if the universal joint is worn or loose, it will make friction noises when rotating; the same component won't produce noise when moving forward due to even force distribution. Additionally, damaged wheel hub bearings are also common—the bearing balls bear weight differently in reverse, causing vibration and noise. You can use a jack to lift the rear wheels and manually rotate them to listen for the noise source; but never disassemble parts without experience, as it's easy to misdiagnose brake system issues. I've encountered several similar cases, solved by applying specialized grease or replacing worn parts. Regularly changing transmission fluid can reduce such wear noises—it's recommended to perform system maintenance every 20,000 kilometers.