If you’re implying that I have “ethics”, you are correct. I distrust those that have proven worthy of distrust, like RP. Mobil 1 reformulated, but had the decency to drop their claims for ACEA ratings, but without doing anything to bring that fact to your attention. In the Cartesian coordinates of ethics, that puts them at “accept, but verify” level. They make some decent products, but you need to do your own homework to be sure the products are what you really want. Their 15W-50 is a good example; used to have ACEA and yielded pretty good UOA. Now it does not have any ACEA, and UOA says it has trouble “staying in grade” between changes in a mildly driven street car (in this case, a Cadillac). Something has changed, and not for the better; but the lack of standards testing ratings implies “caveat emptor”…………

I would just like to add that I've used Royal purple 10-40w in my boxster before and it ran great and I've used it on my other vehicles and after about the 2nd-5th oil change I would notice the engines would run alot smoother...

I remember pulling off my valve covers in my old Mustang to adjust the valves seen the rocker arms and metal body of the head were dark brown... as if the years of use had left a brown/blackish stain on the internal engine parts. Months later and 2 oil changes later using Royal Purple, I had to replace the valve cover gasket and i noticed all the internal engine parts under that same valve cover (even the underside of the valve cover) were CLEANNNNNN, no more brown burnt oil and fuel stain was found on the engine.

I mean it looked like a low mileage engine on the inside of the engine on the surface. So I give it my thumbs up especially now that they have 0-40w which is the recommended oil weight.

Fair enough.

:cheers:

My 2001 came new with 0W-40 Mobil 1,why change?

It uses no oil between annual oil changes (75,000 miles on it so far).

My advice after hearing these arguments for 40 years? Use an approved oil and change it annually.

IMO anything else is nothing more than a waste of your money.

Wow. Never fails to amaze me at how emphatic people get when talking about motor oils!

I will give some backing to the notion that the current Mobil 1 is not the same Mobil that we've all been buying for the last decade. I will also agree that Royal Purple is a bunch of marketing fluff.

As for what's going in my car: Lubro Moly. Has Porsche's blessing, and is made in Germany to boot! "C'mon, you know the Germans make good stuff." :)

In a final closing point, in my opinion, unless you're buying the cheapest Walmart branded stuff you can get your hands on, any of the modern oils are fine in your car provided that you change it more often than every 20k miles.