PO733 AND PO734 ON 98 GRAND CARAVAN WHERES IT GET THE INFO FROM TELLING TCM AND PCM WHAT TO DO

Question

I just bought this van when I got it the only issue was shifting between 3rd and 4th once n a while so I pulled pan and serviced it shifted a little better. just a few days ago getting off the freeway I seen the rpm jump turned stereo down I hear a high pitch whine/squealing sound that changed with rpm check engine lite came on in shifted into n then back into d could feel it going back in gear got home and connected my diagnostic tool the only codes retrieved r po700 po720 po733 and po734 trouble shot output speed sensor circuit wires and connectors tested good replaced failed sensor tip of sensor was covered with metal shavings checked transmission level oil was bright red and no burnt smell drove it with radio off when at idle I hear this high pitch whine/squealing sound put in gear noise goes away until put back into p or n position I haven't clear dtcs yes don't remember how /what resets when goes into limp mode also I shouldn't clear codes until mechanical done

Answer 1

P0700 Transmission control system malfunction Mil requested

P0720 Output sensor circuit malfunction

P0733 Gear 3 incorrect ratio

P0734 Gear 4 incorrect ratio

This is internal transmission failure, The high pitch sound is the transmission underdrive,The evidence is the metal shaving that you have from the output sensor,A rebuild or new is the only solution.