the Example vehicle got front wheel pos on Y 0.03 of the model and rear wheel at Y 0.02 of the model and it seems to be shaking at some of world Y level
and i dont know what is the cause of it

(as you said to move it to Ticket)
https://cdn.discordapp.com/attachments/1068115144657354805/1146008378162827274/Minecraft_1.12.2_2023-08-26_16-53-56.mp4

Going to say this is related to the mystery issue Vehicles in multiplayer make players shake while on them. (Issue #1408)
I know that issue existed but it appears Git deleted it recently.