Coobie
I have the X-Monitor also the highest temp I ever recorded was last summer Aug 2004 in 97*F outside temp was 161*F showing on the X display. I was pulling my 28ft TT. I have always questioned mine reading to low, according to it being tied into the factory trans sensor.
Unloaded this time of the year, (summer) it normally shows 146*F to 148*F
According to my reading of the 2003 owners manual after 15 miles of normal driving the fluid should be 180*F considered hot normal checking it in "N" too hot to comfortably hold between the finger tips. Warm fluid considered 125*F.
Is your sensor located in the hot line, I'm still a little confused on where the correct location should be, some say hot line,some say pan, I don't know myself. At least if I see mine rising in temp some I usually just been adding 20 or 30 degrees to the reading I'm seeing on the X to get actual true temp.
Tony