Q: Transmission made grinding noise when I shifted from park into reverse or from drive into reverse

After the engine revving issue the third attempt to leave and see if it would do it again truck would not go in reverse went into gear but would not move and a grinding rattling noise was present until I took it out of reverse made a little when I put it into park which now was not not holding truck from moving down driveway. However if I put truck into 4wheel drive it would not grind and it would move in reverse??? This is the point in which I checked transmission level come to find it was well into the hot area and transmission was not up to temp by a longs hot. So I drained and checked condition of fluid and as it was pouring from drip pan drain plug it was being filtered into container through a clean coffee filter basket with white filter so I could detect any floating debris. Tryed again and would make noise and not move unless 4wheel was on but after driving reverse came back as did park? And continues to work even to today but still revs up will try TPS & peddle sensor check