Transmission trouble?

Your transmission and torque converter is still within the 3 year 36,000 mile warranty if it is a Chrysler factory remanufactured transmission. That warranty covers your transmission and torque converter (parts and labor) against defective materials and workmanship and so I see no reason for concern or distrust of what they are telling you. But if it was bench rebuilt by a transmission repair shop or someplace like AAMCO and had only a 1 year warranty then I can understand your distrust. I expect that the diagnostic trouble codes logged with the check engine light is P0700 and P0740 and so if you let anyone other than a Chrysler authorized dealer do the previous work and the warranty has expired, then now is the time to take the vehicle to a dealer shop and have the transmission checked by a tech who is Chrysler specific trained.