So I have a 2006 Silverado with 250k miles. Fluid and filter was changed every 50k since new. I've never had a single issue with the trans not shifting right, but it was time to change the fluid.
I had trouble getting the pan out as I forgot how difficult it is and I didn't have the tool to get the shift linkage bracket out, so I forced it out (always a good idea...) In the process the gasket got caught around the 1-2 and 2-3 solenoids, it pulled on one of them, and I manually "actuated" it I guess you could say. It didn't looked damaged or out of place at all.
The fluid was still pretty red, no excessive metal or anything, all looked great except for this strange acorn like thing sitting in the bottom of the pan. I could crush it in my hand, it definitely wasn't metal.
Does anyone know what this is? After the fluid and filter change (OEM parts) it won't shift into first gear... It seems to if I manually put it in first, but I'm not sure if it's really just in second. Once it gets up to speed it's fine, and shifts though other gears fine. It gave me a CEL after driving for a minute P0756 (shift solenoid B performance or stick off)
I plan on replacing the 2 solenoids this week, and not driving it to prevent any more damage. Any help is appreciated!
