First things first, make sure the tires are at 33-34psi COLD. Also, see if the behavior is different when it is not so windy.I also noticed the same understeer with my HH '08. I don't have this problem when driving on the same roads & highways with my Bimmer or Ford Escape or Mazda MPV. So I know its not the roads I think its an issue with Toyota cars because I had the same problem with my '89 Camry. BTW, I also have the Toyo tires with the HH.