How can you tell If you need to replace your fan clutch?

Thanks
Dave
1986 , 560SL

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Dave

If, after driving through stop and go traffic with 100dF ambient conditions the fan is easy to turn by hand you need a new fan clutch. Should be real stiff under these conditions.

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Jim

Seems obvious, but don't forget to turn the engine off first!!!

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KenP

1996 S500 W140 Coupe