Well then I guess we will agree to disagree, or not. Its good that you can quote a book from amazon but it still doesn't support your assumption tbo, what does it say about modern oils in older engines exactly? Any quotes you would like to add? (I would also love to borrow it, btw)[
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One of the main issues with engine oils and its ability to lubricate is not water but fuel dilution, water tends to get boiled off, fuel dilutes oils making them thinner and less effective. Oils come with extensive additive packages to help deal with these issues, generally speaking the top oils have the most R&D put into these packages, to cope with the issues you highlight. One of these is an oils TBN (Total Base Number), the higher the number the better the oils can deal with acid build up over time created during combustion. As said top quality synth oils have high amounts of TBN, perhaps a TBN of up to 15. Most semi synths or minerals oils would probably have a TBN of 6-9. So to say one will last just as long as the other is not entirely correct, generally speaking the top grade oils will be able to deal with fuel dilution, acid build up, etc, more, because the manufactures have designed them to do so, but this obviously is at a cost.
Another advantage of boutique oils (suitable for the road) is that they are not subject to the same emissions restrictions that other oils have to abide by, oil manufactures are free to produce oils that provide max protection, max amounts of ZDDP, etc. Do you know if your oil contains enough ZDDP? How many ppm of zinc? Or you just hoping for the best? I do, its about 1300ppm in my oil which is enough. I also know it has a a healthy TBN of about 12. A HTHS score of 4.6, which is nicely over the ACAE A3B4 minimum for xW40 oils which is a HTHS of 3.6. All these are good indications of how an oil performs, not just at lubricating but in dealing with acid build up, fuel dilution. What have you learned from your oil? Does it meet the ACAE A3B4? If so then good, if not then maybe you need to buy better? (You can get semi-synth oils that meet the A3B4 specs that are quite affordable too).
Ok I may overspec my oils a little but surely this is the safe way to go? Why under spec as you do? Porsche have used synthetic oils as factory fill
from 1992, that means the last 944's (and all 968's with essentially the same engines) to come out of the factory came with synthetic oils, 21 years ago, yet you state its overkill and still use semi/mineral. Porsche recommend 'modern' synthetic oils in our 944's
now, yet you state its overkill and still use semi/minerals. You dont have to buy the latest Nano Tech oils from Millers to benefit from synthetic oil, but for those that do its piece of mind. Why put all that hard work and money into our cars and then skimp on arguably the most important bit? Your assumption is that your oil is
probably good enough, well, thats not good enough for me, I want to know its more than capable, whatever I do with it, all year round, on track, off track, 2700m up a mountain, in -5 conditions or 38Ëš in the south of France. It certainly not pouring money down the drain, its good practice for piece of mind. As you know my car is no garage queen, the car is not abused, its meticulously maintained, I put the best oil I can find in it and I drive it hard and often, just as Ferry intended,
knowing the oil is more than up to the task.
I think we are at both ends of the argument, fact is many people would benefit from a decent oil, mineral, semi-synth or full synthetic that fits in the middle ground between us, its certainly a bit of a minefield knowing what to get. If asked I will suggest people get the best they can afford, suitable for their engine, and their needs.
BTW my fuel bill for last year was about £2336, my oil bill about £75, if you want to save money cut down on the amount you drive, but skimp on engine oil? Really?
Edd
