I have a 2013 GT, Manual, with 3.31's. All the mustang's I test drove before the one I currently own had 3.73's and felt a lot more powerful than this one. I have been looking to get 3.73's installed, but hear a lot of people complaining about how 1st gear is too short and bad fuel economy. Currently 3.55's are on sale this month from http://www.americanmuscle.com/yukon-355-1113gt.html for $130. Does anyone here have 3.55's? What do you guys think?