<E36> Thunking noise problem of the week

["Sanders, Ron" <rls5@xxxxxxx>]

My 93 325is with 85,000 miles is becoming the Ultimate Driving (me off the
edge) Machine.  About every other day, I hear a voice-level rattle/thunking
that appears to be coming from the rear of the car.  However, it doesn't
occur every day and once the temp warms to about 60F it stops.  It seems to
happen when driving at a steady speed on straight, fairly smooth surfaces,
not during left or right turns.  Braking or accelerating do not seem to be
related, although the increased noise during acceleration could mask the
sound.  
So far I've checked/replaced/tightened the following:
poking and prodding every corner of the rear suspension and driveline
with/without wheels weighted
trunk contents including jack and spare
shocks and mounts replaced
anti-roll bar and brackets
bumper cover and trunk panels
exhaust brackets and shields
half-shaft u-joints and boots
e-brake cable adjusted
rear seat area checked for looseness
And yes, I even stuffed myself into the trunk while my wife drove around
laughing her ass off!  Have a go at this one.

Ron Sanders
93 325is
92 525i
86 325

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