I am interested in lowering my 2018 F350 CC LB 4X4 using Sulastic Shackles any thoughts?

 

Nothing wrong with Sulastic Shackes, I believe their intended use is more for ride comfort, not to adjust Ride Height.
An inexpensive option would be to Exchange the Rear Leaf Spring Block with a Shorter one.

 

There are these

1999-2019 Ford F-250/350 Rear Lowering Shackles

A few of us have been interested, but we can't find any members here with them. I am going to give them a call.

 

 

They do list an 1 1/2" lowering kit to go with the shackles.

 

I've got it on my consideration list - my 7" adjustable hitch is at the lowest setting and even my 6'2" self sometimes find the tailgate step nearly too high to use if not parked on level ground.

These trucks are huge and if you have crap washboard cement roads this is something you might want to look into, I know it is on my radar.

 

 

Do lowering shackles affect load capacity as opposed to going the route of shorter blocks? Seems that they could...

 

Their site and information says no-