i really doubt it was due to the temp diff. if this were the case, then guys who live in areas with very cold climates will crack their mirrors all the time. think of it like this...how cold do you think your mirror got??? i know in cali (san fran) a few weeks ago, it was like 40's. and for you to get your mirror colder than this is pretty hard. anyway, if the heated mirror caused your crack, then i would assume mine should have cracked also. maybe it's something else. just my opinion...
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2001 IS300 Graphite Grey
94 Supra TT/6-speed/HardTop
90 Integra
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2001 IS300 Graphite Grey
94 Supra TT/6-speed/HardTop
90 Integra