my VX new untill like 10 or 12,000 miles got 400 miles per tank then 300...then 200...that was like 10 miles per gallon highway and less city.

Then I modded the crap out of it and now it gets about 13MPG. I agree...I shoulda bought the biggest V8 Turbo Diesel Truck I coulda bought for the same price of the VX and got better mileage.
Replaced everything from Fuel filters, MAF, O2 sensors, Pcv, cleaned EGR, manifold gaskets, ECU, coils, etc..you name it.... even installed 4.56 axle gears. I have never got the original mileage back only inproved the down fall with mods.

The VX has been my worst financial investment, but my best hobby/mental investment