Originally Posted by W5KVV
I'm willing to be it's the leaf spring bushings. They'll squeek like crazy. You might also check the sway bar & trac bar bushings (if still equipped).
Basically anything rubber is suspect.
^^ X2 on this. Was the main reason that I switched all of my leaf spring bushings out for the grease-able kind. If its the same as what happened to mine, the bolt seized in the metal bushing and what you are hearing is the bolt rubbing in the shackle hole.
Once replaced, not only is it quiet, but it gives a lot more flex to the suspension when its off-road.
'87 YJ, 4.2L built and bored, 8" of lift, 8.8 rear, AX15/NP 231J, Tom Woods drive shafts, Flat fenders, 12,000LB winch, Custom bumpers, Rattle can paint job. Never completed...