MiQ207

Hi all, let me first say I've been a long time lurker and gained most of my XJ knowledge from reading posts on forums like this one. So, thank you all for the help.

About a week ago my '96 XJ SE (156,xxx miles )had a large leak from the quick disconnection that connects the trans cooler hose to the radiator. The plastic clip in the quick disconnect failed and caused the leak. From my understanding this is a pretty common issue. I bought a pack of replacement plastic clips, installed, and that issue is fixed, no problem. I then went to refill the transmission fluid and was told by an auto store employee that AFT +4 was the correct fluid for my jeep. I filled the trans and took it for a test drive and the trans was not happy...grinding, rattling, and slipping...especially when accelerating from a stop. After doing some research and seeing that dex/merc was actually the proper fluid I began to think the issue might be the type of fluid. I drained the ATF+4 through the drain plug and replaced with Valvoline dex/merc. The shifting is now very smooth but the distinct grinding, rattling sound when accelerating from a stop is still present, and the jeep has started hesitating/stuttering at low speeds when I am slowing to a stop. I was hoping to get some ideas for diagnosing the problem before having to take it to a trans shop.

Here are a few more details.
-There was no (apparent) issues with the transmission before the leak occurred
-The trans fluid I drained was a light brown color and did not look/smell burnt
-The new trans fluid seems to be at the right level...I checked in neutral on flat ground after slowly working through the gears a few times
-The rattling and hesitating/stuttering only occurs at low speeds <15 mph. Seems to be only in 1st gear...once I am in 2nd, 3rd, etc there is no noise and the shifting is smooth.
-The rattling is much more pronounced when in 4wd low

Anyways, any ideas about what might be faulty?