Cece,
Sorry to hear about your issues with the VX. I'm sure it's incredibly frustrating, particularly when things seem to keep going awry. I hope you don't have to sell your VX, but would totally understand if you do.
As for your grinding; have you checked the fluid in both the transfer case and the rear end lately? I don't get a grinding noise, but when I let off of the gas I tend to get some gear noise coming up through the shifter for the four wheel drive system. I have an after market shift knob, and I think it amplifies the gear noise. That noise happens only on deceleration and I'm guessing it's because as the weight of the VX shifts forward it puts stress on the gears and I can then hear them meshing. I don't think it's a problem because it's always made that noise, even after I had the transmission and transfer case fluid changed.
I know this sounds silly, but I also get a wicked noise from my tires when I let off of the gas at highway speeds. Again, I guess it's because the VX's weight shifts forward and pushes the tread on the tires into the pavement differently. That doesn't sound like your problem because you said that you guys had the VX up on the lift and it still made that noise.
Oh, another possibly silly question; have the u-joints on the drive shafts been lubbed?
I would check (or have it checked) the fluids in the transfer case and the rear end to make sure that there is enough clean fluid in there.
Just my two cents.
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