08 King Ranch with a supercharger, freshly rebuilt 4R75E with many updates and a moderate shift kit. From a dig in D (does not do this when shifting manually into 1st) transmission acts like it goes into neutral momentarily, then tries to engage when at high rpm's then disengage and engage. You can imagine what it sounds like (rev, whistle, slam, squeal then repeat until you let off the throttle). Not sure what is making this happen but it didn't start until I got the built transmission back from the shop.
I have the supercharger 93 tune where I like it but the transmission is about 99% complete. Just need to get rid of the neutral type flair in drive from a stop light. I need to get some confidence behind the transmission before I can let the wife take the kids get groceries with my rig.
Attached is my current tune: 2008 King Ranch 5-25-2016 new trans TM.hpt
93 octane supercharger tune: shreds the tires while accelerating in first, chirps 2nd gear and continues to pull hard, third gear kicks like a mule but no chirp. Fuel shut down at 99 mph. (It's a 6000 lb full sized four door truck).
Thanks ahead of time for anyone that can answer or help me fix the D flare.