The shop that mounted and balanced my BFG AT tires had a problem balancing 2 wheels on my truck. So after a few months of dealing with it, I decided to go to a different shop to get them rebalanced. The owner of the shop recommended that he install "Equal" drop in balancing sand/powder. I was sketical at first, but he only had two really anal people come back for weight balancing instead of the Equal. After he was done, I hopped in the truck and went down the highway at 90mph. To my amazement, the vibration was gone. I guess the big rigs have been using the stuff for years. The tire shop has installed it in motorcycles as well as trucks with huge mud tires too. The website is International Marketing, Inc. if you want to read up on it.