performance gain with a predator tuner and transgo shift kit? on a 2002 auto gt

 

Unless all of the local shops you can use tune diablo only, get a SCT xcal2 instead. The SCT is a better handheld with more options and IMO much better tuning (generic tunes).

I used to use diablo, but after constant problems w/ the tunes I went SCT. Alot of this probably had to do with the shop doing it, but I have had more consistant luck with SCT and SCT shops.

If I had an auto the first thing I would do would be a tuner/gears, and a tranny cooler.

With the diablo/sct you should be able to firm up the shifts and change the shift points of your auto, so IDK if the shift kit really is nessicarry. I would get the handheld first and see how it feels.