I have a 97 GT with large miles (172k+) and have just started having tranny problems. At this point I haven't done much to remedy except change the fluid and filter. My problem is that when the temp gauge on the dash is under 210 the shift from 2 to 3 doesn't happen......unless I take my foot off the gas and drop the RPMs to under 1500 or sometimes I have to go over 3k while it's at this temp to get it to shift. But when the temp reaches 210 or above the car shifts hard but accually shifts. Any clue as to what's going on?