lobuxracer

iTrader: (2)

Did you loosen all the bolts and retorque them in the new neutral position after you lowered the suspension?

JDMV8

iTrader: (6)

The car has been lowered for 7 years and no noises ever came from the back. I re-installed the rear sway bar endlinks with no preload recently. Might try taking off the sway bar completely to see if the noise stops.

lobuxracer

iTrader: (2)

Nah, not what I am asking. If you didn't reset the neutral position with the lowered ride height, the bushings were under constant stress and they failed because they were stressed. It's pretty common when people lower their cars, and even most shops fail to do this. If you have rubber bushings, you absolutely must loosen all the bolts holding them captive and tighten them at the new ride height if you want the full service life from the bushing. Otherwise, you get the problem you had. Bushing shredded internally and is making noise. I have nearly 200k miles on my car, and the rubber bushings in the rear are still all just fine.

JDMV8

iTrader: (6)

Oh I see. The suspension was installed preloaded for the most part. However, I only have a few rubber bushings: the top short arm with clevis, the bottom arm with clevis (trailing arm or trac link) and their corresponding spots on the knuckle with rubber bushings. Everything else is spherical. Also a new observation: after closing my rear passenger door kind of hard, I recreated the noise. I tried doing it again, but the noise didn't come back.