2007 Chrysler Town and Country Torque Converter or Just Chr

Thanks for the reply. We just changed the fluid, dropping the pan so only about half, and changed the filter about 3 weeks ago. We replaced it with ATF+4 Full Synthetic, approx. 5qts. The previous change appeared to have also been done with synthetic. We also had the computer re-flashed. At that time the shop said there was nothing wrong with our transmission. Two weeks later my husband was doing some preventative maintenance and disconnected the battery for about 30 mins. We thought we had accidentally blanked the computer. We took it back to the shop, no codes except the battery disconnected. The shop test drove the van as they had done just two weeks before and now we suddenly have a torque converter issue. Is it just the computer re-learning or something to do with having the battery disconnected. I admit there is an occ. Roughness during lock-up now, how did this happen in just two weeks? Shouldn't it have coded if there was a problem? I also noted on forums that other 2007 Chrysler owners had similar problems, had the torque converter replaced and still had the problem? Is it really the torque converter, the computer, or just because it's a Chrysler?

Thanks, you have been very helpful!