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
It sounds like the problem is in the transfer case. The fact that you have to put it in 4wd to move the vehicle tells me that it is in the transfer case. You either have a problem where it will go into 4wd but not completely back to 2wd. Have the transfer case shifted to and from 4- wheel drive at least once a month to help lubricate all the components and keep them from getting stuck in one position when you need them. If you want to have this looked at, a certified professional from YourMechanic can come to your car’s location to inspect the noise and advise you on a repair.