no worries, you're good well above that. it says to not open at speed beyond (i forget exactly what) so you're good. at those speeds with a window just slightly down in the rear you are moving a TON of air in the cabin though - pretty ridiculous, haha!145....track, is that the local expressway? We've got a few of those around :lipsrsealed:
I've been shutting mine if I go over 55; figured that's what it said lol. Guess I'll have to test it out now.