2001 T&C transmission "bump" while slowing

I have a 2001 Chrysler Town and Country with 152,000 miles on it. The transmission was rebuilt at 120,000 miles, and I’ve not had any issues until recently. Two weeks ago it started having issues of not going into gear on random occasions and had an odd “bump or hard” shift upon stopping. I checked the fluid finally and found it was 2 quarts low. I added ATF+4 then unhooked the battery for 20 minutes. It seems to shift OK, but the “bump/hard shift” is still there. It only occurs if I go over 35mph. As I decelerate it “bumps” at around 30mph. I have two questions: How did I manage to burn off two quarts of fluid (there are no visible leaks) and what should be my next move? I’ve read plenty of posts, but none have the same “bump” shift from high gear going down. I see a lot of people replacing parts they later find out does not solve the problem. Am I better off letting a dealer run a scan on it, reflash the shift points....etc? Advice????

You need to quick learn the trans computer. It basically forgot how and when to shift when u disconnected the battery. You can wait it out and just keep driving it till it fix's itself or take it to a shop that has a scanner. They can quick learn it from the scanner. As for the leak, Check the cooler lines to the radiator. They leak all the time but they seap into the body cavities around the radiator!

i wouldnt wait to work itself out, i've learned in having a 2001 before to take it to the dealer and have them take care of it, the quick learn thing. also they may have software updates for your transmission through your pcm, i had 16 software updates on that 2001 and some involved the transmission communications...