[triggerthetruck]

Hi ...well I think I just fixed what I found out is called death wobble... Its worth Googling it...and there are even Youtube clips to watch! I think Ive fixed it by making sure everything is tight and sweet underneath...EVERYTHING!! If it moves...not in the right way..REPLACE IT....or tighten it up.
In my case it seems it was just a little too much play in the steering box. I have to get a new steering damper and thats on order, but, having had another thread going elsewhere on this site Ive found out a lot of things I didnt know....basically check everything. In your case I think it likely to be true that a steering damper will maybe apply a bandaid to the problem, but it wont cure it if other things are wrong...and steering is one of those things thats quite important on a vehicle.