NEED HELP Gmc lost all gears while driving

[David14b]

Hi I have a 1989 gmc sierra and it lost all gears while driving and I know it's probably the pump but when I took of pan and filter off there was square metal pieces in it so my filter my question is can it be vanes from pump rotor is this possible

 

[Mooseman]

That square piece is the magnet. It's to capture fine metal particles. Black sludge and some fine particles are normal. I would assume this is a 700R4 transmission, the predecessor to the 4L60E so no electronic controls. I see no metal bits on that magnet you pictured but if there were, that is definitely not a good sign and would likely mean a complete rebuild even if it is just the pump as those bits would have destroyed stuff along the way.

 

[coolasice]

Hi I have a 1989 gmc sierra and it lost all gears while driving and I know it's probably the pump but when I took of pan and filter off there was square metal pieces in it so my filter my question is can it be vanes from pump rotor is this possible

How many square metal pieces?