You can probably try forcing some lithium grease in between the leafs and maybe where the bushings are. Hell, even poly bushings squeak, that's why they give you that lube with the bushings before you install them.
2003 Ram 1500 QC Hemi Lonestar "Big Red" (Mods list in profile)
2006 Charger R/T "Little Red"
Sarcasm - it beats killing people