The ball joint where the rear lower control arm connects to the axle carrier is the one that usually makes noise when going over bumps. Squirt a little WD-40 into the joint to quiet it temproarily. When repalcing it, do the left and right sides.

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1986 300E (3/2002) Rear ended and totaled (10/2009)
2000 Xterra (5/2000)
1992 400E (11/2009) -Sold
1986 300E (12/2009) - Sold
2004 E500 Wagon (6/2013) - Sold