Fan Blade Assembly Wobble !!!!
 

My 350SDL appears to have play in the shaft which looks like it connects fan blade assembly to the viscous coupling. From the W126 diagrams, it appears the coolant pump drives the viscous coupling and the viscous coupling drives the fan blade assembly.

If this is accurate, any play is likely a very bad thing, right?

Is this common occurrence? In any case, it looks like I need to replace the viscous coupling, right? If I get that far, should I replace the coolant pump (130,000 miles)?

Would appreciate any advice on my troubleshooting accuracy!

Thanks!