2000 mountaineer 5.0 v8 awd vibration coming from front end

[Summajet]

I have a 00 mountaineer 5.0 awd, roughly 225,000 miles. Has a vibration coming from the front end. Took it to a shop and they said vibration/noise definitely coming from front end. Vibration seems more when accelerating and above 60 ph. Tires are balanced and front end alignment is good. When accelerating and turning the wheel left or right it has no effect on the vibration lessening. I did have the front axle yolk rebuilt about 2013. The rubber boot is intact and not torn or ripped off. I have a spare yolk I got from a local junk yard last year. Was thinking of replacing the current yolk with the junk yard one and see if there is any noticeable differences. I thought I had read a good experienced machine shop can weld on a new part to the rive axle yolk? Anyone else have this issue and if so what was the fix?
Thanks

 

[crunchie_frog]

I have the AWD transfer case go bad and it made sort of groaning noise and some vibration. I guess you could try removing the front drive shaft and driving it on the same terrain and at the same speed where you get the vibration now and see if you learn anything from that. I have also had a front wheel bearing go bad, some vibration but mostly noise.

 

[Summajet]

I drove it hits morning and going uphill at about 55mph it started vibrating really bad and groaning noise like gears grinding. I slowed down to 45mph. Got off interstate and on secondary road drove about 45mph. Growling stopped but vibration still there. Did you rebuild yours or have a shop do it? Any idea what the parts cost and also what on average a shop charges to rebuild the case? I was thinking, i can remove it and take to a shop and have it rebuilt. Other than disassembly and reassembly, is it hard to align the gears in the case up?
Thanks