I'm not impressed by SOAs on Cruiser axles. I think SOAs on swb rigs are unstable unless on wide, full-size axles. Swb SOA rigs aren't ever as stable off-camber as swb SUA rigs, but won't be dangerously so on wide axles. SOA conversions can be tricky from both a mechanic's competence and engineering standpoint.
I think far too many 4-wheelers ruin a swb rig with SOAs. FJ40s need SOA advantages far less than other swb 4x4s, IMO, because FJ40s have fairly long springs with a decent width compared to CJs and other swb rigs. FJ40 spring design lends itself well to SUA lifts. The many leaves of FJ40 oem and SUA lift springs also resist axle wrap– the cause of much carnage on 4x4s.
SUA 4"-5" lift springs with many progressive leaves, tapered & diamond cut tips, and poly pads ride better than oem springs, IMO. Better than old, worn out oem springs,anyway.
HFS springs and quality custom springs like from
Alcan Spring have good ride quality and resistence to axle wrap. Alcan informed me that they can make front springs with less or more arch in half of each spring assy to compensate for any castor altering effect of longer than stock shackles to negate the need for shims between the springs and axle perches.
In the long run, it's all in what compromises you want to make. A rockcrawler SUA lift FJ40 sacrifices some boulder crawling capability while a rockcrawler SOA lift rig sacrifices some off-camber safety and also more dependablility against carnage due to the increased stresses on steering, frame, and knuckles. And, as mentioned, SOAs sacrifice more of the contents of one's wallet.
IMO, today's wheelers think they need all kinds of extreme mods to tackle everyday obstacles. Needing extreme mods to boulder crawl is one thing, but I've heard wheelers say one can't get thru the Rubicon without lockers and at least 33" tires which is incredibly ridiculous when one considers that tens of thousands of FJ40s, CJs, EBs, et al were making trips thru the Rubicon since the 50s (60s for FJs/EBs) shod with skinny 31" tires, with no lockers, and on stock suspensions. Shoot, grandmas drove thru the Rubicon in stock heeps before most of us had drivers liscenses. I'm all for cool, functional mods, but some dear folks need to learn to drive off road with open diffs before they think of making mods.
Wise attitude. I can do my own brakes and most general welding but leave welding steering brackets/componets to trusted pros. Does anyone have any suggestions for a good Cruiser shop ner Mozzio?
Btw, I disagree with the idea that power steering should be done before suspension. I think both should be considered together since PS design is driven somewhat by suspension design such as pitman arm length, SR incorporation (I'm against

), any body lift used (drives steering intermediate shaft length), etc. Even installing poly body bushings makes a small difference over worn rubber. Planning is good.