Somewhere back in my past I remember someone telling me that it's possible to stop a belt from squealing by rubbing a bar of soap on it. Anyone else ever hear of this? Probably the quickest and easiest test.

Might be a solution, but in my thinking, rubbing soap on it would

LUBRICATE the belt. Therefore the SLIPPAGE would still be present

even if the noise disappeared.

I would tend more toward a product called Belt Dressing or its

equivalent, which would help a belt to gain traction without unduly

tightening the belt, thereby risking frying the bearings. That's what

we used to use at Bob Sharp's years ago; maybe there is something

even more state-of-the-art in use nowadays

FWIW, ~Rick~.

Thanks for all the comments.

I'll try looking into the fan belt and tell you guys how it goes later.

Check the fan clutch. If it is stuck the resistance it creates will cause the belt to over power it causing it to squeal. WD40 will help with the belt squeal. Look at the sides of the belt. If they are glazed, replace it. Once the belt gets hard spots on it, it will slip, to some degree, for the rest of its life. (fan should rotate freely by hand with the motor off)

Not all 280z's have separate belt tensioners. My 280 had and A/C (which I took off). It just ran off the crank and was adjusted by moving it over on the mount.

Your car, like mine, has/had so called 'dealer' installed AC, his has factory which would have the tensioners or idler pulleys.

From your pics, it looks like you do not have a belt on the A/C so that variable is gone. Like Frank said, check the tension on the Alternator Belt. If you still have a squeal or "other" noise, then check the Alternator bearing and then the Water Pump. Check the Fan Clutch for excessive play when the engine is cold.