I rebuild the trans probably 8k miles ago and today while getting off the highway the durango doesn't want to shift. I get it down the street and park it in the driveway. I look underneath and while its running in drive im dumping tons of trans fluid. It looks like its coming from the converter area. The car will move under its own power but now it has problems shifting. I checked the trans fluid and its way over full but I don't remember filling it all that high. Any ideas what may have just happened?