X,
I have this same problem! Mine started a good while back after a 120 mile drive. Could not for the life of me track it down. Still haven't actually!
I did notice that if the engine temp got around the "M" in normal, the problem would rear its ugly head. Since winter has set in, I since made a shorter 45 mile trip once and did it again. The temp gauge did not leave the "O" in normal.
I have changed my fluid as well. Also, the drive chain as since broke since this problem started. I was told that the shop that worked on it did a complete rebuild, but I don't think they did. I see no evidence of the tranny even being removed.
As for the engine problems being related to this... Right now, I really think anything is possible! I have had a miss during acceleration for a month or so. This weekend I am putting some Ford Motorsports 9's on there. I have checked and regaped the plugs two times since their installtion 5K ago.
I promise, if I find out what stops my tranny problem I will let you know.
P.S. The only code that I have is the good ol' PO420. Yeah I have replaced the secondary bank 1 o2 sensor.
