Description / Abstract: Purpose. To verify quiet, robust performance of front strut top mount assemblies when subjected to moisture and cold temperature while steering.

The noise mechanism is strut rod coning relative to the top mount. Refer to Figure A3 (Appendix A) for definition of strut rod coning. Strut rod coning occurs during steering and suspension travel. Top mount assembly to be evaluated includes top mount, jounce bumper, boot (if secured between jounce bumper and cup), jounce bumper cup, and rate washers.

Applicability. This procedure will apply to all passenger vehicles using MacPherson type front suspensions.