Why does the Corolla feel unstable and swaying at 120 km/h on the highway?

[LeReed]

The reasons why the Corolla feels unstable and swaying at 120 km/h on the highway are as follows: 1. The car's shaking and floating sensation is a feedback of its high-speed stability. 2. It is mainly related to factors such as the chassis, suspension, tires, weight, and wind resistance. 3. The higher the car's chassis, the higher its center of gravity, leading to poorer stability at high speeds on the highway. 4. Tire grip is also a contributing factor; wider tires have a larger contact area with the ground, providing stronger grip. To summarize, the main reasons can be categorized into four points: 1. Wheel balance issues. 2. Four-wheel alignment problems. 3. Environmental influences. 4. Uneven tire pressure.

[McAshley]

Once when I was driving my Corolla on the highway, as soon as I accelerated to 120 km/h, the car body started swaying left and right, like being on a boat, which was really nerve-wracking. Later, I asked a friend to help check it out, and found that the main issue was with the tires: uneven tire pressure, with the left rear tire underinflated; uneven tire wear or improper wheel balancing could also cause this. Additionally, the suspension system had aged and loosened, such as failed shock absorbers or worn wheel bearings, causing wheel instability and shaking at high speeds. Weather factors can't be ignored either, as strong crosswinds can exacerbate this problem. It's recommended to first pull over and check the tire pressure and tire condition. If no obvious abnormalities are found, go to a professional shop for a four-wheel alignment and wheel balancing test to ensure safety before hitting the road again. I've now developed a habit of checking tire pressure every three months to avoid danger at high speeds.

[DeDavid]

I feel noticeable shaking in my Corolla when driving at 120 km/h on the highway, which might be due to inadequate daily maintenance. The car is most prone to shaking when the tires are worn out with flattened tread patterns or underinflated. It's necessary to visit a repair shop to check the tire pressure on all four wheels and perform a balance calibration. Other possible causes include loose suspension components, such as damaged ball joints or shock absorbers, which often result from prolonged driving on uneven roads. You can also conduct a preliminary inspection yourself: use a tire pressure gauge to check if the pressure is consistent across all tires, and visually inspect the tires for bulges or deformities. After addressing these issues, the car will feel much more stable at high speeds, saving you money and giving you peace of mind. Regular minor maintenance can prevent major problems.

[AlanLee]

If the car is shaking violently on the highway, it's crucial to slow down and pull over immediately, as this is very dangerous. Possible causes include unbalanced tire dynamics or deformed wheel hubs, especially common in older vehicles. Suspension system failures, such as leaking shock absorbers, are also frequent culprits. I usually recommend visiting a reputable repair shop where they can quickly diagnose the issue using specialized equipment. Don't delay addressing the problem to avoid compromising vehicle control and causing accidents. Safe driving is paramount.