I have a 2001 Silverado 1500. Turbo'd. Has built 4L80 swapped into it. Was driving to work today and noticed a wierd vibration noise traveling thru the body of the truck then all of a sudden a big pop sound. Now tranny will not move, will lock in park so output shaft is good, disconnected tranny line and started vehicle, has line pressure so the input shaft is good as well. So something broke internally. Anyone have this issue before????

 

Sounds pretty serious if it started vibratings and then popped.. If the pump is good and output is good.. then might as well go ahead and pull it.

 

pulled the transmission last night, removed the converter and straight up pulled the input shaft right out, found that the input shaft actually twisted with a very nice clean break. got lucky, no other damage was found. ordered new shaft and required gaskets, seal, and shaft o rings. should have the truck on the road again by tomorrow night