The rear shock mounts on all 1984-2007 3-series/M3/Z3 are
known for premature failure, particularly when used with an
aftermarket suspension.
Initial indicators of failure is a “clunking” sound which
will eventually lead to complete mount failure... and even
damage to the sheetmetal of the shock mount tower, requiring
expensive bodywork repair.
While various bearing and urethane alternatives have been
devised, many of these are only sufficient for racecar use due
to increased noise, vibration, ride harshness, and short
service life.
The "ultimate" solution comes directly from Meyle,
the manufacturer of many of BMW's original components. Their
"HD" (Heavy Duty) version features a revised conical
center section that makes it virtually impossible to push
through (see cutaway picture above). The result is a durable,
quiet, and trouble-free mount at a reasonable cost.
