Has anyone heard of a way to test the viscous coupling in a Syncro?  I am
contemplating the purchase of a Syncro and would like to be somewhat
reassured that this rather expensive (I keep reading ~$4000 in this ls)
repair will not be necessary shortly after purchase.  Another LS member
thought that there was but was not sure of the details.  Any help would be
greatly appreciated.  Thanks,  Kevin