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@rockola1971 said, black dust is a bad sign, if in quantity at the bottom of the pan. You're also going in and out of limp mode (3rd and reverse only).
Did you continuity-test all the solenoids when the pan was off? Visual inspections are fine but only tell half the story...
You need to find the source of the electrical fault that's putting the transmission into limp mode first. Once it's free of electrical problems, only then will you be able to appraise its mechanical health.
My gut tells me it's coming out sooner rather than later but could be wrong...