You first post dont make much sense.
If your tires look like this \ / then preload aint going to do nothing for ya.
First off this \ / is a bad description. Are they towed in? tipin at top? wheel bearings loose?
If the knuckle is so loose and sloppy that it lets the tire tip out then you have a problem. First off when its wore out the tire tips in not out.
Second, preload is not gonna help a bad feel. If it feels like poo then its got damage or wear.
If its smooth and loose it can be brought back.
If its tight a rough, taking away preload is going to make it loose and rough.
Its not rocket science, its a knuckle bearing that never ever spins a full rotation ever in its whole life.