I don't agree with automatically using the factory torque specs on aftermarket polyurethane bushings and their smooth-edged sleeves. Just too many variables over the stock rubber bushings and their serrated-edged sleeves. If you take that into account each time you do springs, you can use your own judgement as to what torque to use.
Basically then, no matter what the brand, the bottom line is the length of the inner steel sleeve.
If it's long enough to stick well proud of the bushing shoulder, then sure, crank 'em down to factory specs. But they're usually short enough that you end up squeezing too tight on the side of the bushing. Doing nothing beneficial, and usually shortening the life of the bushing and giving the truck a more harsh street ride as well.
So I would take each instance individually, and once the tires are back on the ground with full weight on the truck, and a few bounces to give the springs that initial settling they often go through, simply run the nuts up until the ears of the hanger/shackle/mount presses lightly against the bushing flanges or shoulders.
If the sleeves bottom first, then torque tightly. If the bushings bottom first, before any metal-to-metal contact, then put an additional 10-20 lbs max on the fasteners and leave them at that. Or even less than that, if the bushings show signs of being crushed.
To do this successfully however, your hardware must be either new, or in good working order so the locking nuts can hold things at this setting. If the old c-nuts are used and can't hold torque any longer (as so many can't after several removals) then replace the nuts with known good locking nuts. Either compression type, or Nyloc style. Either works.
That's what many of us do, and so far it's worked out perfectly for many years.
Paul
