New Noise - WD Hitch or Rear End?

Came home from a trip tonight with my 1986 29' Soverign, 2012 Yukon XL 1500 and original Reese WD hitch. The trailer was moderatly loaded and set up exactly as I always do it (bar tension). Part way home I pulled in for gas and I had this LARGE continuous noise as I turned the truck at low speed. It was sort of a grumble rumble type noise which I have never experienced after thousands of miles. First I thought it to be lubrication where the trunnion bars mount into the head. After greasing and readjusting the chains the noise remained. I loosened the friction sway bar and no difference. As soon as the TV & trailer headed straight the noise disappeared (at 5 to 80 mph). Once I got it into my neighborhood I took off the sway and trunnion bars and the noise went away.



Has anyone experienced this? I'm still not ruling out my TV rear axle but for now I'm assuming the Reese hitch. Any recommendations to isolate the problem?



Scott