sorry they are self balancing.that said even though u passed mot(mechanical movement)the brake opperation could be mechanically unballanced.the pad self adjustment works off the handbrake opperation.if one side lags it will bias the other.cure by resetting caliper pistons with special tool and hand brake cable fully of(loose)fit new pads,and using the disconnected caliper lever opperate lever as manny times as it takes to tighten pads onto disc.reconect cable and set free play.bleeding rear calipers while ur in there wouldnt hurt either.
caine
June 2008