Dave, Sounds like AMSOIL Propylene Glycol, only purple coolant I can think of. It is supposed to have amazing anti-corrosive properties to it. Let us know if that's it. Maybe some of the infrequently driven cars can be converted over to it if it works out good, as far as anti corrosiveness goes. Supposed to have the same cooling properties as traditional ethylene glycol coolant with better protection for engine components. If that isn't it, maybe the PO added a bunch of aftermarket additives? Joe O'Brien 2524 & 16634 To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/