Vibration has been an ongoing issue for me. I purchased new tires(Falken Rocky Mountains AT/S when I purchased the vehicle. I had them balanced six times(in a matter of 2-3 months) by Discount Tire, including a Road Force Balance and they couldn't get it right. I complained enough where they swapped them out for a set of Michelin LTX AT2.
Issued solved..........until I had them rotated and balanced at 8k miles. I went back to Discount three times and they again, could not get it right. At the suggestion of another member here I went to a local shop and they have been working with me.
The first time they indexed the tires, which is moving the tire around on the wheel to try to get it to balance better. It worked a little but the vibe was still there, so I took it back last night. One tire was sufficiently out of balance again. Also, since they are lug centric, we tried torquing the lugs while the vehicle was in the air to see if this helps. I'll have it on the highway later today to know if the issue has been resolved.
My wife thinks I'm crazy, she doesn't feel it. I say my vehicle is just not the same since I had them rotated. It drives me nuts and I feel your pain.
Make sure they are using the Haweka adapter. It is a MUST with our wheels. Our wheels out lug centric, not hub centric. If the shop is not using this adapter make sure they are, or find another shop that has it.
4Runners.org - Balancing Your Tires: Haweka Adapter
Also a good read:
Vibration Problems
Good luck, and let us know how it goes.