Item synchronization is still very poor across clients. For example, one player will still see 3 tires while another player will see 4 on the same vehicle.
In this same category, false duplicates are still occurring on other random items as well. For example, if I drop a box of ammo on the ground for a friend and that friend picks it up, I will still sometimes see a box of ammo on the ground. The false duplicate can actually be picked up by any players who see it though and if a player does that, the item will be removed from the inventory of the player who has it in their personal inventory.
Even more troubling, the false duplicates of tires can create solid barriers for traveling vehicles, independent of whether of not the person driving the vehicle can actually see the tire on the ground. Our bus was put out of commision for more than an hour because of one such instance. A false dupe of a wheel that was actually attached to the bus ruined the front two tires when the driver ran into it.