How hard do they turn (new) after you torque them down? If you can't turn them using, say, three fingers on the wheel studs, they are likely too tight. When I put my Moog hubs in and torqued them to specs, they turned way too hard. My solution was to torque them down to five pounds over, them loosen them off and torque them to five pounds under. They were still a little stiff but tolerable. Any bearing set that turns stiffly is going to generate heat, to much heat and the bearing rollers (balls) or races self destruct.
I'm not a hub expert but spent years working with bearings in machinery of various sorts.
I have no doubt in my mind if I would have torqued them down to spec, and left them as they were (turning way too hard) they would have likely burnt up before they wore in.
I swear, the first time I torqued mine down I felt a bearing slip. Leads me to beleive the depth spec for the bearings were off from the factory. I've talked to other guys who think the same.
Another thing you may want to look at are the inner seals, the seal race is on the shaft and the seal itself is on the hub (for Renix). If the race wears out (or moves, it slides on the shaft) the seal may not contact the race or may contact way to hard and burn up. Pretty much the same setup as older Dodges use and a trouble spot. The first time through water and the hub fills with water. They are sealed bearings, but does anybody really know how sealed they are. I always clean out and fill the inside of my hubs with grease and make sure the rear seal is in good shape. Likely not necessary , but a little redundancy never really hurt anything and just may save a bearing some day if the bearing seal fails.