Hoping you all can help with an issue I am scratching my head about. Recently, not every day, driving on highway at speed, my temp gauge rose to about 3/4 range while going up a hill. Transmission dropped to another gear as normal to help speed up the hill. At the top of the hill, transmission went back to cruising gear and temp gauge went back to normal and stayed that way all the way home. It has happened only twice in 3 weeks and only on highway. Below are more details about car and what I checked:
2014 Fusion Ecoboost SE
117,000 miles
Antifreeze normal and system not leaking anywhere
Transmission is not leaking
Temp sensor tested and seems to be working
Car seems sluggish on highway but normal off highway
Only does it while going up a hill on highway going about 75