Well I decided just to put it in and hope for the best. So far so good, I have put about 600 miles on it and no problems. The only change that I have seen so far is the newer trans shifts slower than the original. Such as when You floor it at 65-70, it downshifts twice instead of jumping straight to the lower gear. I remember reading somewhere a while back that the valve bodies where slightly different, and I noticted that the connectors were different colors (original white/new black). So I guess I did well for a working 545RFE on craigslist for $250 bucks that works well! BTW, I had the Durango lifted 6" with 35's, doing some serious offroading when the front differential ripped the bellhousing on the left side as well as the starter motor clear off. I reattached the starter to the sheetmetal between the engine and trans and drove it for two years without problems. Any questions or comments feel free to ask.