there is no such fluid as dexron atf+3. the only chrysler fluid available is atf+4.
symptoms of a clogged filter is, while driving the transmission starts slipping. shut off the vehicle and wait, then restart, it will drive ok for a little bit then start acting up.
question is why is the filter clogged? debris in the pan which would come off parts in the trans (clutches, torque converter, bearings, gears, etc.)