Hello, I have a 2010 f150 4.6 and had the transmission rebuilt but it keeps laying over into hot region on cluster and the fans come on. Had the use box replaced and the mechanic keeps telling me it won't overheat bit after 7 miles gets hot. I need help!

 

Suppose we start with one possibility.
If the trans cooler is plugged/restricted it could contribute to the problem
What we need to know is what failed in the trans and if it sent junk into the cooler and maybe plugged it.
A good rebuild includes flushing the cooler, do you know if this was done?