Annoying Shimmy

[RIGSTAR]

I got this shimmy that ive recently got. its small but a little more than a crack in the road, it comes intermittenly and seems to be getting a little heavier. i rotated my tires, rebalanced them, new tirod, its still doing it so i dont think its tires or suspension. Sometimes it comes when im slowing down into 2. always at high speeds. The deerfoot just got new ashpalt so i know its not the roads. A bout 2 months ago i had a rear left axle seal leak, got a new one and filled up what i lost but i couldnt imagine anything with that would make this shimmy.Im riding on Open Countrys, 37's. i got an 8'' in fabtek lift on an 06'. Would this be something in the tranny? or rear end?

thx boys

 

[Burn Down]

Hi & welcome to the site.
Did you check your front wheel bearings. My truck picked up a vibration (shimmy) at about 75-80 mph half way through Canada headed home to Idaho. Put it on the lift at my dads shop and had about 1/2" of play in the tires on the right & close to a inch on the left. Installed new wheel bearings vibration gone. Just a thought...