I have a buddy with an LLY that is having issues. He has a PPE stage 5 with an ML converter. He has broken his flexplate and flywheel it is shifting so hard around 54 mph, it barks the tires when it does it, or drags them not sure which. I had Rob build a custom tranny tune to lessen the torque converter lock and smooth out the shifts as much as possible and it is still shifting VERY HARD, only at this one shift. The truck does have a 6" lift with 35's on 20's and is running tunes built by Rob. I am trying to figure out if his low fuel pressure could cause it to shift this hard or if we need to have my builder pull it and check the tolerances in the C2 and C3 clutch packs. it does the hard shift no matter if it is in t/h or not so I don't think it's the converter. Anybody else have an issue like this before they resolved?