Just last week I hit 140 in my CTS on some open Iowa highway. Thing was smooth as glass! I love this car! One of my tires has minor damage which I dont know if it was there before I went 140 but I assume it was because I didnt hit anything or my dealer did it when they had it that night. Well either way, no speed tests until i get new rims and tires! I did blow the doors off an eclipse last night though. I romped on it next to him and then let him catch up for a sec and then romped on it whenever he got close, LOL!