I have used oil samples for years. We get them from AV Lube on the net. The last ones I got were $16 each. You get a little bottle and an info form to fill out, then you just mail it in ( w/ 4 stamps). You can send new oil if you want and they will measure the zinc. They also measure the additives in the old oil. I used them to protect myself from the frod stealer since I didn't want to use 5w/20 in my F350. Other than that, We just do them yearly to moniter equipment. 3 samples can tell you all you need to know- new oil brand, old oil at change, and old oil at extended change if you want. They tell me when you increase detergent level, you may see an increase in wear metals, so the third one can be a second chance for the new brand. Hope this helps somebody. - Lou, a past but hopeful 300 owner. ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: mailto:Chrysler300-digest@xxxxxxxxxxxxxxx mailto:Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/