I have a 1999 2500 short bed with 45,000 miles. I have been having problems the last number of months with the vehicle swaying while driving at about 40 mph or greater. It feels somewhat like both back tires are flat and it "mushes" as I slightly rotate the steering wheel back and forth. I have change tires, bought new shocks, had the front end aligned, replaced some front end parts, all at the suggestions of various shops (dealers and private) I have visited. None of the "fixes"worked. Now it is being suggested by another dealer that the steering gear ($650 plus install) MAY solve the proglem----no guarantees. This suggestion makes a little more sense to me, since I have had noise (sounds like low steering fluid sounds) in my steering since the rig was new. I need some suggestions please.