So I made my first haul with the new to me truck. Pulled over after 15 miles just to look over things and rear end was pretty warm could touch and thats about it. I left my temp gun at the shop so I dont know exactly what the temp was but I was pulling about 17k. Unloaded and got back to shop got heat gun and the pinion bearing area was 150 degrees the lowest part of third member was 138, thats pulling a 8k empty trailer. So I know it was hotter when loaded, lets just say 170, temp was a 60 degree day. Seems a little hot to me. What are you seeing rear end temps at? I replaced the pinion seal and dont know what I torqued it to but I know I looked it up. 

Seems pretty normal.  160 deg solo, 200+ deg in summer towing heavy.