rear leaf spring differences

[manyholes]

hey guys, just getting parts ordered for my suspension and was wondering if there was any difference between w250 diesel and w350 springs(diesel or gas)??

ordered up 4" front springs
jungle's rear shackle/spring mount kit(said to be 4 3/4" lift)
nitro shocks
waiting for input prior to ordering rear springs from local shop and u bolts

im not afraid to spend a few bucks extra to get the truck right the first time instead of putting more leafs in latter and ubolts. thanks

any input on bushings?? rubber or go to ureathane?
with the rear springs, i haul normally at minimum 100 gallon slip tank full, tool box worth about 150lbs and a 12000lb winch in the bed(its on recever mount). occasionally, i do have a secondary 100 gallon tank full in there too. not sure on the wieght of diesel per gallon. i do pull my boat (4000lbs combined with trailer) and looking at getting a 5th wheel in the area of 10-12,000 lbs i do not want this truck to squat under load so that my lights are shinning at the moon, this is why i went with the shackle lift rear to use factory heavy springs vs flexy lift springs.

[ciamcoop]

Do you not want to use air bags to compensate for your load? What's the shackle lift? Did you flip the shackles? I don't think I'd flip the shackles on a tow rig, that's asking a lot of the bushings in everything to keep the axle from moving side to side. I guess you could add a panhard bar to keep it lined up. I think if you want to avoid the rear from sagging with a good load you're going to want some kind of adjustable system. Air bags or air shocks. A 12k lb 5th wheel will probably have around 2000 lbs of tongue weight.

[manyholes]

the shackle kit is from jungle jim on Ramchargercentral he's on here as well.
heres the link to the rear parts
http://ramchargercentral.com/jungleshdd ... p-hangers/
http://ramchargercentral.com/jungleshdd ... ckle-flip/

because the truck will be support a fair amount of wieght in it at any given time and i dont have onboard air yet, i didnt want to rely on airbags for when im in the bush.