On a side note - when I worked on the GMT-800 they had SICK knock-back so they moved the claipers from 12 o'clock tp 9 o'clock. That helped but were still getting some cos the pads were long and the shaft wasn't stiff enough to prevent rotor deflection, so GM being the cheap bastards they are CHAMFERED the pads
Thus as you wore down the pads knockback would come back. Fuggin' stupid.
I fixed that on my H2 axle buy making the THICKEST 9.5" axle shaft you've ever seen
