Doug H

Hi, White987S - No, the oil I use (Delvac 1 5w-40) is a "mixed fleet" Group 4/5 fully synthetic Heavy Duty Engine Oil (HDEO) for Commercial use I have used this lubricant for many years and over many millions of kms in a variety of engines - including many Porsche engines It is a very different lubricant to Delvac 1300 15w-40 (mineral) that you mention Delvac 1 5w-40 has a very close relation in M1 Turbo Diesel Truck 5w-40! Regards Doug

Hi, saaber1 - Correctly interpreting UOAs is a complex issue. Universal averages are at best a guide. Trending one engine or a group of engines of the same specification is the most accurate way to monitor oil condition and wear metal uptake rates. Wear metal uptake can then be reasonably assessed for "spikes" that may indicate some engine abnormality Wear metal uptake rates are not linear and it is wise to remember that they are accumulative in real terms. So it is only wise to judge the rate at the OC point - interim tracking invites many wrong assumptions. Certail lubricants have a tendency to show higher levels of some metals than others but there are sound chemical reasons for this. They DO NOT indicate abnormal engine wear!! I have tracked many Porsche 928 engines and I have a significant database on this engine family. Most 928 engines are very similar (metallurgy etc) and very few are modified with add on oil coolers etc (not like 911 engines). In the case of the 928s the OCI uptake result is 1ppm Iron/1000kms To accurately assess one lubricant against another requires a very strict set of controls to ensure accuracy. Each "conditioned" lubricant must start at a similar point and tracking is now done by Radioactive Tracer Technology amongst a number of other available processes. It is beyond the scope of UOA results which are really only a very accurate way of determining the condition of the lubricant! In field trials CUMMINS state that around 800k miles is needed to assess a lubricant in service and that end on end lubricant changes (Brand/type) are simply a waste of time. After using UOAs since the 1950-1960s course I share this view entirely I hope this of some interest Regards Doug (with Delvac 1 5w-40 in my Boxster)

Hi, saaber - Do not be concerned about the iron levels at all Regards Doug (BITOG)

Hi, fdss - Your quote "There are better oils than Mobil1. And they're real synthetic! Do some research" This is a very subjective comment - any REAL facts to back it up? Regards Doug Hillary

Hi, wvicary - The basis for Porsche engine lubricant Approval is the current ACEA Quality standard A3/B3 Porsche then extend some of the ACEA tests and they have some specific tests of their own. These include anti-foaming and a number more Since 1994 it has been common for Euro makers to modify the ACEA tests as "after tests" to ACEA compliant lubricants. This is based on special engine family needs, field testing experience and of course Warranty claims data and etc Prior to this Manufacturer tests were "in house" devised and or extensions of the API's tests Despite all the hype about the API's SM Quality standard (mainly through misunderstandings) some of Porsche Approved oils are already rated SM/CF but of course none will be ILSAC GF-4 compliant I hope this is of some interest - if I can locate any more of the data I have on the Porsche test protocols I'll publish it Regards Doug Hillary

Hi, Amsoil in not "the best" oil but simply one of many good lubricants. At least their 5w-40 Euro Formula product is a MB Approved one Many Amsoil lubricants tend to thicken with use and this is not desirable in a modern engine Comparing the performance of lubricants can never be a subjective task and any one of the 100 odd Porsche Approved and Listed ones will perform the same as another. Any variance will indeed be at the periphery and be very minor indeed Mobil 1 products marked "synthetic" are indeed full synthetic (Group 4 or 4/5) in what had become the true sense of the word. Porsche's specification mandates only engine lubricants that are Group 3 (semi-synthetic to many) or of a higher Group. Some Mobil lubricants like the non approved one that I use have a complex ester content and are rated as Group 4/5 benaslan - Comparing one lubricant to another by using a single pass UOA is at best "interesting" at worst it is totally misleading! Any late model Porsche owner who choses not to use a lubricant from the Porsche Approved list should do so with considerable caution. Unless of course the specification is "better" than those on the List - a lot of knowledge is needed to determine this point In particular the Porsche test protocols include prolonged tests for viscosity control (at both 100C and 150C) and for anti-foaming performance. Anti foaming performance is critical in engine with more than one oil pump and where the lubricant plays a significant "hydraulic" actuation role It is wise to remember that their is no "magic" oil of any Brand Regards Doug Hillary