Not sure what tuner ur using. But with my bullydog on performance my EGT temp are in the 800's on highway not towing. An when u step on the GO pedal ur temps will go up.

While towing a 7300 to 7500 pound load my EGT temp have been up in the 1200 to 1290 range.

I have hit temps of 1380 unloaded before. Just all depends on how hard an for how long u hold the GO pedal.