Slee's 4" springs are great, but if you don't have the weight on your truck you're probably not going to like them that much.
The other thing to consider is that an unloaded truck will be very high with Slee's. If you correct caster and the driveline for that height, then as you add weight you'll need to go in and readjust the axles or compensate for the loss in height.
Starting with OME and a lower height, you correct the caster and driveline once. As you add weight you add spacers and with enough weight you then go to Slee's and hopefully be back where you started with the OME unloaded.
I'd think that 850Js and 863s on an unloaded truck would put you close to where I am loaded.
One thing about the suspensions, they sell well used.
The attached pic is the truck with the 30mm spacer added.
The other thing to consider is that an unloaded truck will be very high with Slee's. If you correct caster and the driveline for that height, then as you add weight you'll need to go in and readjust the axles or compensate for the loss in height.
Starting with OME and a lower height, you correct the caster and driveline once. As you add weight you add spacers and with enough weight you then go to Slee's and hopefully be back where you started with the OME unloaded.
I'd think that 850Js and 863s on an unloaded truck would put you close to where I am loaded.
One thing about the suspensions, they sell well used.
The attached pic is the truck with the 30mm spacer added.