[Scenario]

Not sure what you mean by "dynamic vehicles." No such thing AFAIK. I use "CreateVehicle()" for every vehicle on the server. If you're loading them properly, they shouldn't be getting mixed-up ID's. Vehicle ID's start from 1 and each time AddStaticVehicle(Ex) or CreateVehicle() is called, that number continues to increase (there's always differences if you delete a vehicle and spawn a new one, though: that will take the ID of the vehicle you deleted if I remember correctly).

If you have some code, it might be a good idea to provide it so we can all take a look!