I will be going through the PVG again next week and the week after for my trip.
First will be AA LAX - MU PVG - BKK and then return KA HKG - AA PVG - ORD. I'll let you know how it goes, but I've never been able to check through the bags to/from the US. Only from Japan to HK via PVG.
One agent told me a few years ago that the US has stricter regulations so the bags need to be scanned at PVG that's why you cannot check-through there, but that might not be true if they allow it from PEK.
Regarding transit tmes, PVG is often delayed. I have 2hr 40 mins between the HKG - PVG - ORD flight. That's enough time if there's no delay, I hope that's not a prob.
Lastly, I heard others talking about the AA transit desk, but with the need to recheck the bags, is there any point to get the boarding pass there as opposed to the normal desk outside?