Pulled a P0748 code

Ok I pulled p0748 code from my 97 dodge dakota has v6 and 155825 miles so I replaced all solenoids and pressure sensor still geting the same code I can shift but only manually overdrive wont engadge I think o/d is computer controled also acts like it has bad gas but not all the time also I here a relay clicking on or off now and then where the fuse panel in the cab but I thought the trans relay is under the hood witch I checked that also by switching it out with one of the others on the same fuse panel
its driving me crazy so I called dodge dealer to put on there computer and they say with as many miles I have I need a new transmission with as much smarts I have I think its not mechanical its computer controled I think its not geting a signal from pcm to trans also does dealer computer pull and dig deeper than my actron hand held scaner can any one help me thanks