Thanks for the advice...never put anything into the tire, shake started as soon as I had tires installed, I have had three different places ballance the tires, all seemed to agree they where out of ballance...all was smooth for about 100-200 miles and then same issue again. Could changing tires affect u-joints...asking beacuse problem was never evident with old tires. I googled my tires and this seems to be an issue with these tires...any recomendations of new tires? Michelin's seem expensive but do receive high praise.