Transmission 1981 generation 2 Camaro Z28

[Greacore]

Hello everyone, trying to find reasons that my transmission just quit working. I was driving uphill, flooring it, and it was like car went into neutral. No noise no bangs, just quit. I have plenty of fluid and I’m sure my pump is working ( I cracked open the upper line going to radiator and fluid immediately started to come out). I have no drips or puddles. I’d like to find out there is something that became unattached before I spend a week dropping the transmission.  It is a turbo 350 3 speed automatic w/o overdrive.  Everything seemed normal until it quit. Was neither extremely hot nor cold. I only drive 4-5 miles to work.  I do drive it like I am 16 but that’s what I’m supposed to do.  Any advice that keeps me from dropping the transmission would be greatly appreciated.