How to Deal with Poor Sound Insulation in Sedans?

[DeAlice]

If the sound insulation of the vehicle is poor, noise can be reduced or eliminated by installing soundproofing materials. A full-vehicle sound insulation treatment can be performed to reduce overall tire noise, road noise, wind noise, and engine noise, thereby mitigating mid-to-high-frequency noise at high speeds. Generally, if the ears feel uncomfortable, it may be due to low-frequency resonance noise. Filling professional sound-absorbing cotton in areas such as the doors, floor, and trunk, as well as in cavity positions, can improve low-frequency noise and enhance comfort. After professional automotive sound insulation construction, vehicle noise can be reduced by 3-8 decibels. The noise at a speed of 100 kilometers per hour is equivalent to the noise at a speed of just over 60 kilometers per hour without sound insulation. You can feel that the engine noise is effectively suppressed, tire noise and road noise are significantly reduced, the audio system's performance is improved, and the overall feel when driving on uneven roads is greatly enhanced.

[Braxton]

My car used to have annoyingly loud noise on the highway, so I researched several methods to improve sound insulation. The simplest solution was switching to quiet tires, like Michelin's Primacy series, which made a significant difference in reducing tire noise. I also added D-shaped sealing strips to the door frames, which cost just tens of RMB on Taobao, and immediately noticed reduced wind noise when closing the doors. Chassis insulation is crucial – I had an undercoating spray applied at a repair shop, costing about a thousand RMB including materials and labor. The trunk and wheel arches are most prone to resonance, so I bought soundproofing foam and applied a layer myself. For the seats, which are troublesome to remove, I hired a professional. The combined effect of these measures is remarkable, and now my ears feel much more comfortable on long drives.

[BlakelyAnn]

The issue of poor sound insulation needs to be addressed at its root. I consulted a professional to analyze the noise sources. For tire noise, switching to quiet tires like Michelin or Continental works well; for wind noise, check the aging condition of door seals and replace them with parts bought from Taobao, which you can install yourself; engine noise can be reduced by adding sound insulation cotton under the hood. The most challenging is chassis noise, which requires removing the seats to lay soundproofing materials. My experience suggests starting with key areas: install soundproof panels on the four doors and trunk, and apply vibration damping treatment to the wheel arches. The entire process takes about three to four days and costs around 5,000 yuan, but the car becomes as quiet as a new one. Regular maintenance of seals can prolong the effect.

[StMiles]

I have firsthand experience with poor sedan sound insulation. First, check the door sealing strips—if they're aged, you can pinch cracks with your fingers; replacing them significantly reduces wind noise. Then, listen for tire noise—switching to quiet tires is the most straightforward solution. For DIY fixes, purchasing sealing strips and soundproofing foam to apply around the door frames is particularly effective. Leave the underbody coating to a repair shop for peace of mind. Focus on the wheel arches, where noise reflection is the loudest. Spending around a thousand yuan can bring noticeable improvement—avoid removing seats as it's too troublesome. Now, I can enjoy music while driving without interference.