Here is a link the the Eastwood ZDDP page. There are explanations and responses from customers to read and at $10.000 a 4 oz bottle (good for 6 qt change) is reasonable. I have used this with with a quality oil for several changes on several cars for years.. I do not use a synthetic oil so can not speak to that direction of thought. John Iowa 300 K... https://www.eastwood.com/ew-zddp-oil-additive-4-oz.html __._,_.___ Posted by: John Holst <jholst@xxxxxxxxx> To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to https://groups.yahoo.com/neo/groups/all/manage/edit For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylang __,_._,___ |