I've posted this before, but whenever I tow our trailer we seem to hit 8-10 mile, 6-7% grades on the Interstates. Pulling my 3600# trailer at 65 mph, the transmission ALWAYS drops down into 2nd to climb these hills at that speed, and, my
TFT has at one time (in the hot summer) hit 225 degrees. The fluid has never seemed "burnt", but I just had it changed at the 60K mark.
Typically, when towing on the "level", the
TFT stays in the 160-170 degree range.
- Jack