So. 2005 F-250 Diesel. 246000 miles. Just did all the head bolt garbage. Last week I noticed that when I was driving over 70 and backed off the throttle it did a loud humming until it was under 70mph. Last couple days it plays this game also around 37-38mph. Saturday I brought Dunny home. Truck did not do its humming (I call it airplane sound) while pulling the trailer. After dropping trailer and heading back out, it started a fairly serious vibration when coming to a complete stop. Not slowing for curves or whatnot, only when stopping completely. Sorta felt like it started towards front and worked its way back and became more violent as it went. Also, the airplane humming resumed. I really, really, really cannot dump more money into this truck for a major repair. Something minor like u-joints or rotors or something would be ok. But if my rearend is done, I don't think I can have that replaced. Not to mention being down a vehicle. Ugh! Just looking for ideas of where to start. I've got a mechanic friend who I'm gonna try and get to drive it but his work schedule is crazy. My mom thinks U-joints but everything I research says you'll notice noise when shifting to reverse and a vibration when accelerating. All of my issues are during deceleration. I had a ton of work done on front end but it's been about 50,000 miles ago. I try to never drive over 50mph with hubs locked in.