Third stage of thinking (or feeling), after tow truck pulled car back on road, next morning I took FJ Cruiser to local tire shop. New tires on rear, re-balanced front tires, mechanic for tire shop says "all good". So, we went on I-80 W - continue to drive to Kansas. It was sunny day, roads dry - normal condition. Drove about 74-75 mi/h for 2.5 - 3 hours. ... And (bingo) "wiggling" back - appears one time, we both, myself and my wife feel it, car just waved a little for a moment ... scary feeling on 75!! ... In a little while - it appeared again, getting really scary... I started clicking down Cruiser Control handle, got speed down to 65, and 60 -- reducing speed - reduce "feelings" from "wiggling effect". At a moment it was busy on highway, I got to right lane, all trucks and cars passing me at higher speed. Even on speed of 60 - "wiggling" feelings appeared (periodically, 30 seconds, or more, no definite pattern of time...).