"Really hot"?

Brakes are dragging!

You're not doing a lot of heavy braking right before you check the temp are you? Brakes will easily put a lot of heat into the hub/wheel even if they're dragging just a little. Bearings - not so much - unless things are BAD wrong. You'd have to crank down on the bearing preload quite a bit - or have totally shot bearings - to get "really" hot - as in can't keep your hand on the wheel very long. Might want to jack a wheel off the tarmac and see how much brake drag you've got...

BTW the 4.4 - 5.5 lbs is for a new bearing and seal. For used bearing/new seal the preload is 2.6 - 4.0 lbs. And you don't even need a a fish scale - just find an object with the desired mass and hang it on a lug bolt at 3 o'clock. I use a gallon milk jug half full of water - hang it on the lug bolt with some wire and turn the preload down until the 4.15 lbs of water won't turn the hub then back off a hair and call it good. This way you don't have to have three hands - gravity takes care of the tension leaving you one hand free to spin and one to tighten...