From part of a previous post: The zero rates I'm currently running to move the front axle forward throws off my caster angle. When moved forward, the axle follows the contour of the spring, tipping the pinion down somewhat. A shim brings the caster back to zero degrees (parallel to the ground) but the spring tends to move on the pad during hard wheeling b/c the studs on the right spring mount d60 don't follow the this contour like a u-bolt would (at least that's what I've been told-which does kinda make sense). Anyway.... With the zero rates it’s not the inch of lift I’m after so much as pushing the axle forward. I like increased the approach angles it gives and it also keeps the tire away from the firewall. Would it be feasible to move my forward and aft shackle attachments forward 1.5-2 inches? I know there’s not a lot of room to move the aft shackle before the frame starts to curve upward, but I could run a little longer shackle to keep the caster angle at zero and the longer shackle could also help with articulation. What do ya’ll think?