Transmission noises and other problems doe it need a rebuild or a shift actuator or?

I have a 2005 chrysler town & country 115,000 miles auto trans. Here is the problem. I just drove the van on a 5,000 mile road trip. While in the mid-west I had some issues. Reverse was chattering, blinding and clunking. Additionally at times when slowing down with my foot off the gas, after the van would down shift into first, (so we are talking less than 10 miles an hours) I would hear a sound that I would describe as a loud ticking noise or ratcheting. This went on and on for three days worth of driving. At the time I wasn't sure if we would make it home as it was very bad at times. Now that I am at home it is acting normally. The transmission has had the fluid and filter changed every 15,000 miles. I have an aftermarket trans temp gauge in the van and the transmission has never been overheated. I have no transmission or power train codes, however I have some interesting ABS codes, that I don't think are related. One code for each wheel speed sensor (input signal missing) and one code for engine module missing. The ABS light went on and off twice during the trip but I doubt that ABS is causing the transmission problem, I am basically trying to deturman if I need a rebuilt transmission or a shift actuator or something else. What do you think?