60-70 steering wheel vibration

So I've this as well as many people on here do and no amount of balancing, road force balancing, ride matching, alignments, or new tires have been able to alleviate the problem. I have seen a couple posts on here about steering flutter and also the mention of adjusting the preload on the steering rack. I found this post for the lexus GS 400's that have the same problem and I'm thinking about giving it a try. Has anybody else tried this and what were the results?

Here's the link I've found to some info :

http://us.lexusownersclub.com/forums/index.php?showtopic=59280

 

Bump

 

I have the same problem, I was told I have a wheel that is slightly out of shape..had to use alot of weight on it to get it to balance as well as a little extra air pressure. As soon as I loose a little air it comes back.

 

I've even had my rim runout checked and my rims are definitely not out of round

 

So no one has adjusted the preload on their steering rack?