Start looking for worn or damaged steering and/or suspension components instead of chasing brake problems which probably don't exist. A loose steering gear center point adjustment would be a good place to begin, followed by a check of wheel bearing preload and kingpin slack. Even sloppy bushings and shackles on the rear springs can let the rear axle shift and giuve you some oddball steering input.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!