A brand new tire could be out of round, it has happened to me, and it's near impossible to balance, so I would have that checked.
Which kit do you get, the one with spacers? If so, I installed my teraflex level kit without disconnecting the track bar. I also didn't torque all bolts to torque specs (I know I'll get bashed for that) and I have no DW... Last Thursday I had to go to Maryland (from NJ) and back in one day. I also have Spidertrax spacers, and I have hit plenty of bumps and a couple of pot holes... no DW. Mine is an 08 with 56k or so miles.
Have the tires checked, move front to back and if the problem continues have them road force balanced. After that maybe a failed steering component?
EDIT: My tires are not 35s, the larger the tire, the more DW issues one will get when something is out of balance or loose...