As a new owner of a Black R/T Challenger with manual 6 speed and 3.92 with 20 inch wheel's . I love it . Best MPG so far is 22.3 . 2nd gear has to be just right shifting into it. Are they all like that. I went from a 6 speed MX5 GT . So it will take awhile to get the feel . Who makes the shifter for the trans.