Does anyone have any recommendations for a balance in the Boulder, CO area? I got a set of General Grabber AT2s (285/75r16) mounted and balanced at the Discount Tire there and I think after 4 trips to two different DT's (one in Broomfield, too) all they've managed to do is move the vibration around. To his credit, the guy at the Broomfield one did say he was going to use the lug adapter during their last attempt but the shimmy is still there. Moving the wheels front to back does change (not eliminate) the vibration so I'm fairly certain that's where the problem lies.

My office moved recently so I'm putting a lot more highway miles on and the 60-70mph shimmy is getting pretty aggravating.