mikgills

95 G30 van 4l80 trans gets very hot climbing mountain grades (220*) then continues to get hotter when descending same steep grades (engine temp goes down but trans temp goes up). verified aftermarket trans gauge with GM tech 1 scanner. Van has the internal & exterior trans coolers. I don't like the trans oil getting that high. Is this increase in oil temp going downhill normal? (this was in 2nd gear-no lock up). Trans has gone into limp mode previously (did not have temp gauge at that time so not sure if it was over temp trans, but it was NOT engine over temp). Reset by pulling ECM fuse and everything was normal afterwards. Never does this on the flats. Changed trans oil and filter after incident.
Does your trans temp increase going down steep grades in 2nd?