Do you have a 99? If so, it's the rear lower control arm bushing cups rubbing against the mounting ears on the IRS subframe. Loosen them, grind away some metal with a die grinder, and apply anti-sieze in the crack. Re-tighten. fixed.
Yes. When the brakes are applied, and going over bumps at low speed. This causes the lca's to flex and the bushing cups rub the subframe. This was fixed for the 01's supposedly, but was a prevalent issue for the 99s
If you crawl under the car and look closely at the rearmost lca bushing, you should be able to see if it's rubbing the subframe ear. Just look at the flange on the bushing cup - it should be shiny if it's rubbing. If it is, that's probably causing the creak.
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