Picked up my 3 yesterday- driving home heard the loudest rattle every time I hit a bump. I freak out. "This is a new car! Did I get a bad batch?" As I'm driving on the freeway I frantically try to figure out what it is. I go thru my mind how I will deal with service center. Can they even fix this? How many times will I have to keep going back and showing the guy, insisting it's still making this noise! It's coming from the passenger side, sounds like the seat? So now I'm driving one hand on the wheel and one hand hold the passenger seat as tight as I can in place to stop the rattle. Wait.. that worked... NOPE There it is again! Maybe it's coming from the window? I roll it down partially, nope, still rattling. I roll it down all the way. Wait! That worked- OK it's the window! Maybe it just needs to be tightened? Wait, it's rattling again- it's not the window! This car is the worst! I get home, immediately go to the drivers side to see what I can find. I move the seat around- there is the rattle! Yep- it's a seat issue. I try to pinpoint where as I move the seat around more and then I find the culprit! The seatbelt is hitting the plastic part of the back of the seat. I try to the belt around, no luck It keeps hitting. But OK this should be an easy fix for service- right? I mean, it's just a seat belt! Although I have read nightmare stories about Tesla service. But I'm a little calmer. And then, wait, what if I move the seat up slightly. Yep. That fixed it. I'm a moron. But very relieved.