As it gets into freezing temps, interior rattles stop in my car.
My wife's toyota-made vehicle is behaving a little differently, panels start rattle when it gets colder. Is there an explanation to this?

 

you know what's funny, I find my car rattling more when the temperature drops! doesn't rattle as much in the summer, I live in Long Island, NY, cold winters and hot summers...

gotta love the 4 seasons!!! and no, I'm not talking about the hotel chain or the restaurant in midtown manhattan

 

Materials contract as they get colder.
Maybe something is tightening up in your car when it's getting colder.

 

my car is oppsite to yours...less rattles when warmer...

 

I am also getting a rattling noise, but it is coming from the passenger side sunvisor/mirror.

Any advice on how to fix this? I was thinking of removing the housing and put a thin layer of foam or cushion behind the mirror.

 

Expansion and Contraction.

 

As previously mentioned, materials generally contract when they are colder. But the story of rattles is more complicated. Materials don't all contract the same amount for a given change in temperature. So whether or not a car gets more or less rattles with changes in temperature has everything to do with how all the different materials are connected. Incidentally, most car manufacturers rely on the flexibility of plastics to adjust to changes in temperature (with the help of strategically placed foam pieces) in order to keep the noise down. As plastics age, they loose their flexibility and are more likely to cause rattles and other noises.

 

I had this same rattle on my drivers side. Told the dealer they used that sealer stuff and its gone.

 

Mine has noticably more rattles when cold. In the summer it's pretty much rattle free. The weird thing is mine happen when I go over a bump or gutter at an angle, as the structure flexes. I thought these cars were supposed to be very rigid. I might check and see if I tightened the strut brace enough when I did the shocks. I may have had the car still jacked up on one side when I tightened it which would explain a lot.