front differential movement
 

I have a 2006 ford f150 lifted 6 inches with a fabtech lift. when i put the truck in 4 wheel drive and move forward and backward i can clearly see the differential shifting upward about 2 inches it also binds real bad when turning because of this, and makes a very loud (clunk) noise when doing these things. i have been on a few websites looking how to buy the bushings for the mount and replace them. the mounts are not broken just the bushings are worn out and i want to know where to get them so i can fix my truck 4x4 before winter sets in with snow. any one with information please help thankss.