P0872 help. I’m stumped

Cqberry3

New member
Nov 25, 2013
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I need some help with this infamous p0872. I bought the truck the way it sits, so I don’t have much of a back story. I’ve read and read for a week, can’t really find exactly what I’m looking for. It’s an 08, 160k miles. Deleted and tuned, pretty much stock other then that as far as I know. When you put it in gear, it goes into first, let it roll 15 feet if that and you can feel it shift through the gears and hang in 4th. The last shop to work on it pulled the valve body out, and sent it to merchant to have them ream the E valve bore. Pulled the VB back out of it this week to make sure no trash or debris had gotten in it, it was all clean, no valves stuck. Took it apart and cleaned it anyways since it was out, put it back it and same result. I’ve checked the voltage at the TCM, it seems fine. The fluid and both magnets were clean, no debris in the pan ether. I have a new PMS coming this evening to try, but I really don’t want to start throwing parts at it. Does anyone have any other ideas? Sometimes it will pop up and say shift range inhibited, other times it defaults straight to 4th without issue. It does have reverse as well, it’s just real slow and bangs real hard once it does go in