[ImperialCrown]

Welcome to Allpar. Using ATF+4 only, right? Other ATF products that don't meet Chrysler MS-9602 can damage these transaxles. It is very important to know what is put in the transaxle during service. Dexron and Mercon are bad news.
I have found that P0740 is a slipping torque converter 'lock-up' clutch (TCC) and that the front pump can be worn as well, causing this code.
P0700 is just the PCM saying that there is a code (P0740) present in the TCM.
Too many technicians got burned by replacing only the torque converter. By replacing the front pump as well, it covers all the bases. The bronze bushings wear on the pump and cause an internal 'TCC apply' pressure leak. Visually you may see some wear.
At 121K, the shop may want to replace the clutches and seals (rebuild) and go through the transaxle, even if everything is still OK. Otherwise they may not warranty the job. Call around and explain your situation. Some shops may want to drop in a reman which saves labor, but may be more expensive and unnecessary. As long as everything is clean and in good shape, a pump/converter replacement should fix this.
Rarely is this an electrical problem and is almost always an internal mechanical wear/hydraulic leak problem.

 

[doeboy]

Thanks for your reply. The cost from the dealer to rebuild was 2500 and from a local shop it was 2200. I plan on taking this car to at least 200k and have taken great care of it. The only thing I am concerned about is if the TC is slipping then there could be metal flowing through the system and wearing down the rest of the transmission. I guess its about should I take a chance and maybe be okay or maybe the other worn parts will stop functioning and I will end up with a rebuild anyway. Ugh. I would just drive it till it breaks, but I have to pass an inspection soon. It would seem the only way to really tell if things are okay inside the tranny would be to take it apart and then make a determination about the TC and Pump replacement. ATF 4 is on the order paper from the dealer so I assume thats what they put in.

 

[ImperialCrown]

I don't know about your state inspection, but if the 'ck eng' light is on or the OBD II monitors haven't completed running after turning the light off, it may not pass.
If they noted debris in the fluid or the bottom of the pan, it might determining how deep of a rebuild is necessary.
The CVI values creep upwards as the clutches wear. There is a threshold for the values and CVI's are an adaptable memory. The 'Clutch Volume Index' is the time in milliseconds that the pump takes to fill and apply a clutch. The TCM can tell when a clutch is filled during 'quicklearn' is the instant when the speed sensor sees the clutch hold.
Most shops would want to do a complete rebuild as they have to warranty their work and want to mitigate risk as much as they can. Having just the converter and pump replaced can be done while the transaxle is still on the trans jack and then it go back up into the car. You might want to talk to them and see what their policy is regarding a 'partial' rebuild. You may have to carry the risk of no warranty if that is acceptable to you.
Front pump bushing wear would be seen as a fine bronze material in the pan bottom. It won't stick to the magnet. The t/converter hub and front pump mating surfaces may look 'polished' from wear.
A cooler flush and TCM software upgrade (if applicable) after the service would be appropriate to complete the service.