Need help with part ID

[glebreton]

I am trying to improve the suspension on 01 Excursion LTD 4X4 7.3L. I got under the rear end today and I see what looks like an add-a-leaf under the stock rear leaf springs. I looked for pics online but most stock pics do not show this extra lower spring arm. I took some pics that are so-so. Can anyone tell if this is a stock spring or an aftermarket assist. The spacers or bump stops at the end of this addtl spring leaf are worn and need replacing. As best I can tell, it reads "565 234" on the spacer. I can't find that as an OEM ford part to get a replacement. I'd appreciate any help determining if this is aftermarket addition and how to find a replacement spacer/bump stop for this lower spring arm. I hope the pics are helpful. Thanks in advance.

[njneer1]

That is the anti axle wrap leaf that comes on an Excursion from the factory. Keeps the axle from windng up on aceeleration or take off.......Excursion springs are much softer than pickups so this was added.......Your springs are likely shot.....check your fronts.......bet you are all over the bumpstops.....