4l80e Lost all gears after pulling cluster
 

Hey all, this is my 1st post here. I recently purchased a 2004 Silverado 2500 2wd. It was quite rough shape. The cluster was not working at all, I know normal issue. This is where it gets weird. I was driving it last weekend, everything was just fine, shifted smooth etc. Parked it. Went in side, took a nap, came back out, turned the key to the on position, pulled the shifter down to 1st, removed the cluster, put it back in park. Then started it to move the truck and I had lost all my gears completely. It also threw code P1810. I can tell it is shifting into each gear, because it changes the RPMs and I see the selector switching under the truck. I pulled a transmission line, started truck. At 1st, it wasn't really pumping much, slow flow then dribbled etc, but about 10 seconds of running, and I notice it started flowing pretty good. I know not scientific or anything, but I don't have a gauge to check pressures. anyways, I put the cluster back in the car, turned the code off, but nothing changed. I have been looking online everywhere to see if pulling the cluster out while the gear shifter was not in park or neutral could cause any issues like this, but haven't found anything related. I don't typically believe strict coincidences, so Its hard for me to believe that my transmission went to crap all of a sudden and I lose every gear the same time I remove my gauge cluster. . Can anyone assist me with what could be going on with this?