I have noticed when I am pulling away from a red light or other dead stop, my truck or trailer makes a whinig noise for a few seconds? Its hard to tell where its coming from, but it sounds like the truck? maybe the tranny? it doesnt matter if I have the tow/haul mode engaged or not. It only last a few seconds and sounds kinda like a medium pitched "whine". Anyone else experience this? It seems to be worse on up hill grades than when on a flat spot.