I just bought an 03 with the 6 speed tranny. I put a bullydog programmer on it and set it on performance. At 100km p/hr, when I drop it into 5th to pass someone, it feels like the clutch slips for a second. I dropped it to the tow mode and it didnt do it. I am thinking I may need a clutch. What is a good aftermarket unit. I tried to buy a centerforce for a 460 powered crewcab I used to own and the tranny shop said it was the wrong application for my needs. I thought a centerforce would be a good upgrade. Any suggestions.