Despite having my '99 Rodeo aligned and wheels balanced 3 times, I still have vibration and control (constant wheel adjusting and wander) issues at speeds above 65 MPH. Both the shop and I have inspected all of the steering components (ball joints, tie rods, etc.) and they seem ok. I don't suspect a warped rotor as I don't feel any pedal pulsation when braking. A significant wind gust can blow me almost into another lane. Steering is tight (no play) when inspected off and on the ground and also at speeds below 65MPH. The control issue seems to come into play when the vibration issue starts - as if one of the wheels were losing some road contact when vibrating (probably true). Shocks are brand new (Gabriel Ultra). Tires are in good visual shape (Kuhmo Road Venture HT).

I'm inclined to suspect wheel bearings but there's no play in the wheels when pushed/pulled and no audible noises when spun.

The shop 'suspects' poor quality tires. I'm doubtful and don't want to hand over $500 for a new set if this isn't going to cure the problem.

Any ideas?