Yes, I too, have heard of adding tire beads into tire but never about adding thin liquid such as Antifreeze+ water.
While I cannot votch for it's effectiveness in a truck tire, I can tell you with confidence that if you attempt to deal with certain mechanical/material defectives by taking the "easy" way out, chance are, it will not save you any $$ in any way.
You know, most of those cheap radial tires are not "balanced" nor "round" right from the beginning. The cheaper, the worst it gets.
Also, if you have mechanical problems such as worn upper/lower ball joints, out-of-true rims/wheel hub, worn wheel bearings, etc. chance are, your car is going to vibrate/shimmy no matter how good your tires are.
Also: not all radial tires are the same when it comes to quality: most European, Japanese, French, UK, Italy, Sweden, Finland, and some US rubber tire casting are of superior quality; on the contrary, some S.American, China, Indonesia, and a few well-regarded US brand name tire castings are crap, IMHO.