Skid/Wheel hop of front wheel when hard braking just before the ABS kicks in, ???

[san rensho]

Originally Posted by woodsman

It's also possible that the brake on that corner is grabbing for some reason. After a short drive stop and check (carefully) the brake and wheel temps by gingerly touching them. Compare side to side to determine if you've got a dragging caliper. You could also jack the corner in question up and see if the wheel rotates freely. A dragging brake can be caused by heavily corroded brake lines ( they will squeeze but not fully release), a broken pad surface or a seized caliper ( in this case a stuck piston). If it's dragging, you would PROBABLY notice a pull to that side occasionally. It's worth investigating as it could suddenly get worse and something could break.

The right side of a Box (or any car) is lighter than the left because the driver is in the left hand seat. So, unweigheighted right side will lose traction before the left side. Pretty simple. If the brake is dragging, usually you will notice a definite pull to one side in any braking condition, not at the edge when ABS kicks in.

[woodsman]

In this case I am speaking from direct experience. I know the RF will usually lock first and why but my DD recently changed and began locking prematurely and violently- with a hop feeling even. It was a stuck piston.