This car is cancollide false (except for 4 invisible wheels). When I unanchor the car, it does not move at all. When I get close enough, the shell and the interior fall through the baseplate (expected), some of the tires fall through (unexpected - all tires should fall through) and several smaller pieces do not fall through (unexpected - all pieces should fall through). Also, kicking around the invisible wheels will move them about 10 studs before they stop (unexpected - they should keep rolling).
On a live place this does not occur, but I suspect this is the reason why my cars are all broken when testing solo.
I can’t reproduce this locally in production studio. Tried accurate play solo (which it looks like you’re using) and start server / start player.
What you’re describing sounds really typical of desynced network ownership situations. Typically where the server thinks the client owns it, but the client thinks no one owns it because of some replication ordering issue. If you get close enough the client will put the mechanism in the “buffer zone” and start simulating it locally as well, which explains why they would stop after 10 studs. You can confirm this by enabling Settings > Physics > AreOwnersShown. If it shows up black on the client, but as the same color as the player on the server, that’s what’s happening.
I only know about this happening when welds are involved and should have been fixed recently. Looks like your model doesn’t have any welds either. If you can give me any more pointers for reproducing this, that would help a lot.
I may have identified a cause of this issue: team create. When I loaded up the teamcreate I was working on and performed the same steps in the video, the same behavior occurred.
It has to do with the method of unanchoring. Using a script to unanchor works fine, but selecting the parts and changing the anchored property in Properties causes the behavior in the video.
EDIT: I wrote a script to unanchor cars when I sit in them and the problem no longer occurs.