I Installed Tien S tech springs a couple of days ago... drove straight home and took her out first time yesterday.. I noticed a small hollow knocking sound almost sounded like a ball joint only when driving on corrugated road... i turned around went back home opened the bonnet only to find a washer sitting loose on top of my shock.. It has ( 55044 AL501 1-18T >NR+BR< ) on the one side of it... is this even anything to do with my car ?? Everything seems tight? My Z is a 04 Daytona blue im from South Africa... Thanks for the help...