Thank you @Les Neilson , I found the link you mentioned, but it doesn't fix my problem.I was browsing a few days ago and found a link to a patch which it claimed would eliminate the jittering when stationary. But I didn't download it and now I can't remember where I saw it. I have a feeling it was in the comments of a youtube video, but I haven't been able to find it so far. Does anyone know about it?
https://acstuff.ru/f/d/20-shaders-patch-reduced-wobbling
My problem is more likely caused by the physical effect on the road/tire than vertical shaders issue.
If I change the camera view and see the car from the rear, I find the car is drifting on the road when I put the car in neutral.