Toyota Repair: 91 Toyota Previa noise in rear tires, rear tires, truck tires

Question
My 91 Previa began making a loud noise in the back two tire areas that could best be described as sounding like I have monster truck tires on the back.  The noise begins after speeds over 3-5 mph and is loudest around 35-40, being more quiet at 60-65 but can still hear some.  It is worse when I turn a corner.  A tire was fixed and reinstalled in the rear prior to this time but the noise seems to be on both sides in the rear.  Any ideas what I might be looking at?  I have 208,000 miles on my vehicle and it is 2WD.  There isn't any vibration that I can feel, just a loud tire/road noise.

Answer
It sounds like there may be some tire cupping, check the tires to see if there is that condition, the tires will look choppy and have a sawtooth pattern on the tread, this may be caused by an out of balance condition or possibly worn shocks or struts which will allow the wheels to lose contact with the road and cause a bouncing effect which can cause this type of tire wear which in turn will cause a road noise.