Thanks for the info Big Z and dochummer, I'm still not sure if it's a bad mirror as we never see the cold temperatures that everyone seems to be reporting in Big Z's link (Louisiana, Never really gets below 35) so I haven't seen the big temperature fluctuations. It just happened once and the outside temperature was around 35 degrees. I will however keep an eye on it and if it continues I will get the dealer to replace. Thanks
