I went to the track last weekend and the best I could manage was a 13.30 at 99mph. During the last pass it shifted harder than usual going into 3rd I think. I didn't think anything of it and when I was on the return road I heard a weird metal rattling type of noise. It came and went a couple of times so I just babied it back home. I haven't drove much since last weekend until tonight. I pulled up into my gun dealer's driveway and I could not put it into Park. It wouldn't go past reverse or drive. I kept trying and it finally went. I left there about 30 mins later and shifted from park thru drive a couple of times with no issues. I drove 30 miles to Kinkos and it did the same thing again and I could barely get it back into park. While sitting at the stop light I let off the brakes and it did not move. I pushed on the gas and it downshifted hard and moved forward. When I left Kinkos there were no issues getting it in drive. The transmission temps did not get over 173. I got to the stop light a couple of miles from my house and it did not down shift again. I ran the codes and got a p1000, p0766, and p2703. Has anybody had any issues like this? I was running the extreme race tune from Innovative. This is my first time with any tranny issues. Oh and I just had the transmission flushed a couple days before I took it to the track. The truck has just under 30k on it. Hopefully I don't have to buy a new transmission. If so guess I'll be calling Suncoast. Sorry for such a long post. The good news is my stamps came back from the ATF for my 3 cans.