Nobody was suggesting that WD40 was a fix for the problem, only a diagnostic tool. If a bearing is squealing due to lost lubrication, WD40 will temporarily silence the squeal and allow you to find the problem.

A less militant approach to replying to threads will serve you well on this forum.

I've never had luck with WD40 finding a waterpump bearing squeal - usually those bearings, which are usually shrouded by the pulley, only squeal as a result of the pump seals having failed and allowing water into the bearing. Most cases, the leaking antifreeze will be found before the bearing starts to squeal.

Agreed with others that removing the belt and spinning the pulleys is the best diagnostic method - but have you ever tried to remove the belt on a W140 3.2L engine???

Shall we now go and consume massive quantities of chicken embryo's?