I would like to add again, just with a little more punch
Yes gears make heat, so do bearings as they destroy themselves from too much preload.
I am not an alarmist, nor do I think you would just hammer the heck out of a pinion nut, but, five 3/8 bolts and the pinion housing comes out as a unit. Set preload on the pinion bearings and you KNOW you are right. It won't change gear mesh, setup, or anything else, it just makes sure you have preload right.
Then bolt the pinion housing back in and drive away.