Changing gear impossible as in, the gear lever wouldn’t move/it wouldn’t go into gear? Or could change gear because as soon as you put the clutch in the car slowed down so quickly you needed to drop back down a gear again?
Yep kind of agree with that diagnosis also, based on the extra information about gears - although normally the screeching noise wouldn’t change with vehicle speed? It would be constant as soon as the clutch pedal is depressed and get worse with engine revs increasing?