Hello again....and I am enjoying the conversation on this subject. Please though...read my comments carefully. I did not say ANY oil will last 25,000 miles. Some extended drain synthetics can and will last 25,000 in the average car. There are many reasons why oil breaks down. Just a few of which are; heat & cold, burn off, Viscosity retention properties, Contamination control, acid control, film strength, combustion contamination et. In every reason listed above, synthetics are considerably superior to petroleum base stocks. I for one feel that extreme service or not, synthetics are vastly superior to Dino oil, and if they don't cost me additional $ out of my pocket.....why not use it? I have the advantage of superior protection, Less frequent trips to the Dealer, Quick Lube, or oil dump station if I do the changes myself. The 3000 mile oil change interval is a real controversy. The U.S. is the only country that uses this as a "standard". Europe is on a 9,000 mile drain interval and will be increasing this soon. Why is the U.S. on 3000 miles? Many feel it is marketing and the oil companies desire to sell more oil? The quick lubers are certainly not going to challenge the 3000 mile change interval. I feel we all need to consider the benefits of synthetics and learn how to best use them. Changing oil every 3000 miles or 3 months is insane and a waste of money, time & oil. I hate being taken advantage of and there is considerable research that says we are being duped by the 3000 mile oil change. If you want a very good resource that delves into synthetic vs Dino oil and exposes the myth of the 3000 mile oil change interval......here it is Email:
info@motor-oil-bible.com