It happens all the time. I've heard it on nearly new foci. Some zetecs are noisier than others. Be sure to use 5w-30 (synthetic preferred).
98.5 SVT
91 Escort GT (almost sold)
96 ATX Zetec (i brake to watch you swerve)
FS: SVT rear sway bar
WTB: Very cheap beater
CEG Dragon Run - October 13-15