Something has got to be wrong with your truck as a 7.9 0-60 on the gryphon is not right at all with that gearing. I can not see the 4.6 being that much of a dog even with tunes! I have 3.73 gearing and 35's I can cut a 0-60 in 7 secs. Had custom tunes, S&B Intake, flowmaster 40 series 2 into 1...