John,
Sorry about that headache.
On the bright side, the above customer found the problem. His rear hub bolt had come loose and the metallic screeching was from the hub and rotor coming loose. I imagine the rotor probably tilted over into the caliper. I have seen that several times.
I don't know who made his car or who built his suspension.
Check your bolts!!!
Important bolts to check!!!
rear hub (see above)
drive shaft
half shafts (I have seen several of these come apart)
ring hear (this used to be a huge problem until we developed our latest 17-4 PH stainless bolts. They are beasts).
motor mounts (both to the motor and to the frame)
caliper bolts (and the rest of the brake system)
throttle linkage (these slip more often than people think if they aren't tight)
differential mounts (both to the differential and to the frame)
all suspension bolts
steering system bolts--even the steering wheel!
KNOCK OFFS! (wing nuts, wheel nuts, whatever you call them).
I've probably forgot a few--please add any that I may have overlooked!
These cars are sometimes driven a bit hard and can use some love to check things out on a regular basis.
David