Greeting, I am seeking assistance to diagnose a loud screeching on my 720 4x4. The screech only happens under load or if I rev the engine high and drop it. The only belts I am aware of is the clutch fan belt and the alternator belt. I have attempted to locate the screech by spraying WD40 on both belts and it does not make a difference. No pulleys seem to be wobbling or bent. The only other belt I can think of is the timing chain, but being that it is a chain I would imagine it should not screech? The screech does appear to be coming from lower end and inside the front of the engine? The belts are tight but I have not changed them yet. Any helpful comments to resolve the issue would be most welcome.