2004 pacifica transmission wont shift itself, why on 2004 Chrysler Pacifica

in stop and go traffic it acts like it doesnt know what gear it should be in, it seems to be sticking between two gears

Asked by for the 2004 Chrysler Pacifica
have you serviced it regularly?? you need to have the trans scanned for any codes for possible failures. it could be valve body or internal requiring removal and overhaul.