Hi SDS,
Could I clarify a few things please? I’ll just add notes to your original paragraphs to avoid any further confusion.
Peter:
I think you are creating a straw man. I don't think I have said there is only one viscosity or brand that is best, nor do I think LN/Charles Navarro is saying that in his article (which i'm still not sure you've read).
It wasn’t my intention but I think this is an unfortunate result of my talking generally about a variety of Porsche engine related issues and not specifically recognising that your interest lies with the M67 engine. I confirm I’ve read Charley’s article a number of times over the last 18 months and I’ve shifted from initial strong agreement to a state of lesser acceptance of some of his assertions. That’s Ok, I accept he is doing this in good faith. I'm not sure I can say about some of the other peddlers.
I am not an expert in oil or engines, but I do read what the "experts" have to share with us laypeople (whether, Doug H., Charles, or Jake Raby of Flat 6). I have decided to follow the recommendation for higher ZDDP oil (regardless of brand) in a 5W40 full synthetic because of the rationale these experts have stated, which sounds logical to me. Further, Jake Raby/Flat 6 builds engines and re-builds blown engines and in the process he advised us that they measure for engine wear and test different oils, brands and weights.
I agree with the approach you are taking by following your engine builder’s advice. I cannot see any disadvantage whatsoever in doing this and I would do the same. However I cannot see how he can provide definitive advice that a high ZDDP/5w-40 oil is going to save your engine from destruction. I think the M67 issues are far more complicated than the type of engine oil used. If he was to say something like: “We’ve had good results with high ZDDP/5w-40 oil in this engine and we recommend our customers use it too”, I can’t criticise. My issue is with the “definitiveness” of the advice.
You or the OP may read their recommendations and decide you simply don't need to follow their advice and continue to use Mobil 0W40, or any other brand and weight and I completely respect your decision to do so. But, you have not addressed the substance of their findings -- which is a 5W40 (in a watercooled) is better than a 0w40 for HTHS, and a higher ZDDP oil provides better protection (based on their own testing and engine build/tear down). Now, at the end of the day, I have no way of proving whether the next 75 or 100k on the clock will be better for following their recommendations, since -- I'm not tearing down my engine now or until it needs a rebuild.
Continuing the “definitiveness” issue further, I don’t think anyone has the hard data, except possibly Porsche, to prove one lubricant is better than another. It’s interesting that Porsche don’t even discriminate between the various brand A40 accredited oils. They say they are all equal. Expecting the various engine builders have access to sufficient engines doing long mileages under controlled conditions to give similar statistically valid advice is I think a long shot.
Since I don't own an air-cooled 911, the best I can say is that I'd go with a 5W50 or 15W50 if I had to make that decision during summer since temps where I live get to Vegas hot (115); and maybe a 5W40 would be fine the remainder of the year.
I agree. I’d also prefer if the oil meets A3/B4 and A40 as well to give me the greatest confidence (and also ensures the important minimum HTHS requirement is meet.) After saying that I’m happily using a HDEO in one car as well (meets the HTHS requirement by virtue of meeting the ACEA E7 spec and 1500ppm of Zinc from a period where I used to suffer from a ZDDP anxiety because I didn’t know any better and was trying to solve a problem I didn’t actually have!) I guess this just illustrates that there are many ways to skin this cat and there are more than one good oil brand and type to use.
Further, since I now have a flat 6 IMS Solution, I'm going to follow the recommendation because this is the weight they tested for their product and there is no reason not to use a 5W40 (other than for winter in Colorado where a 0W40 may provide slightly better performance where temps do indeed fall to -28 degrees F or colder for short periods of time).
I agree. I also agree with your approach of using a plain bearing to properly solve the IMS bearing engineering issue. I don’t agree with many like Wayne Dempsey of Pelican fame that suggest that the IMS bearing issue is caused or can be influenced by oil selection.
So, no argument here -- not selling anything to anyone. Just making the best informed decision I can make recognizing that Porsche has changed its recommendations over time in terms of oil and weight, ambient temps, Mobil pays a lot of money to get that sticker placed on the Porsche cars; and we have to recognize in the US that CAFE and emissions plays a role in what the manufacturer recommends.
No argument here either, just trying to separate fact from fallacy and ease the anxiety that I and many enthusiasts have over oil selection. My suggesting that we should use A3/B4 oils definitely does not support to use of low SAP’s and CAFE and emission reduction style oils for our cars. I think Porsche changing its recommendations through the TSB process over the years is just a reflection that we keep driving their old cars for decades and oil technology has progressed in this time. I’d like to use Mobil 1 too but it is prohibitively expensive to do so here in Australia and this is why I have been seeking suitable alternatives based on some sort of sensible logic.
Enough said.
You don’t really mean that! Please take my comments as happy banter, open to (preferably constructive) criticism. At the end of the day it is only engine oil we’re talking about!
Regards
