Stacy known problem with lifts and front driveshafts. Fab Tech includes a new drive shaft. Wheel balance and tire balance can also cause vibration. You can remove the front shaft and drive it to see if vibration goes away(drive in 4 hi lock). If not front shaft has to be tires. If you have more than 2 ounces on a tire have them rotate the tire 180 degrees on the rim.
Pulling while breaking = breaks on one side grapping harder than the other. Mud in calipers, stuck caliper piston (can't think of the right word) or pads worn or fluid on pad. Have the dealer check the breaks and calipers.
