02 wont shift into OD? help please

ok i guess last week some time i was on the highway and noticed high rpms like 3.5k at 55mph when normaly its about 2- 2.5. then turned the car off and back on and was fine for a while. now wife drives the car and told me she is having the same problem. why wont it shift into overdrive? is it the TCM?

Needs a speed sensor,there are 2 of them and get it checked for codes.The good news is the 1998 to 2004 transmissions do not go out which are bulletproof and most yards do not get calls for them,they sit on the shelf