Pirelli PZero Nero GT 225/40 ZR18 92Y

Hello, I have above mentioned tires on my Astra-H station wagon on the rear axle. However, I have an absolutely bad driving behaviour. With moderately fast cornerings the ESP light flashes up each time. The tires are about 1000km on it and slowly they should be “imprisoned”. Today I pushed it once and it is definitely the rear axle that starts to break out. Is not a racing car now, but I want to survive an evasive maneuver on the highway. The tyre is so bad on a dry road, there’s no such thing. I’ve already looked for feathers and dampers, but I didn’t find anything eye-catching. Can you do something wrong when mounting that provokes such a behaviour (height)? When driving, you don’t notice anything, but that’s probably less to be expected on the rear axle. Is the tyre so bad? Does someone have similar experiences with this tire? Thank you. Greeting Metalhead