Three repair shops including Dodge dealer where I bought my van told me I needed a transmission overhaul on my 2007 Grand Caravan with 52k miles. Cost $2500. Last resort paid off big. I went to the Advance autoparts got the diagnostics test. Code was PO 740 for a torque converter clutch cylanoid. I took the chance, bought the part for $180 and low & behold, problem fixed. The part took 2 hours to install. Needed only a 10mm and 3/16 deep socket set. Yes, dodge mixes metric and standard hardware. Last thing, be sure to disconnet the battery to re-boot the computer.
Initial symptoms were a sudden problem. Transmission would slip, lunge, and jerk when shifting between gears.
Hope this saves you tons of $$$.