Chrysler Repair: 1996 Sebring conv, v-6 ,auto trans slips in OD, sebring conv, independent shop

Question
my convert with 138000 miles runs and drives if I leave it in 3rd range gear. If I move it to D range the car will not hold in overdrive and begins to slip then shifts to low gear as I slow down.....do I need a trasmission repair? can it be repaired with out removing the engine?

Answer
Hi Max,
The best way to find out would be to readout the transmission computer to see if it has recognized a fault and coded it as a 4-digit number in the memory. There is a plug under the dash which a code reader is inserted to get the code. An Autozone parts store will often do it for free or an independent shop may charge about $40. So do that, get the code numbers (and what they say the title of the code is) and then let me know and we'll go from there. It might be either something requiring rebuild or it could be something that can be fixed on a part that is fixable without removing.
Check the level of the fluid in the transmission and use only ATF +4 type if needed. Don't over- fill it.
Roland