Johnn, I've been doing some reading on synthetics over the last few years. I am not an expert, but I do have some observations. There is actual documented evidence of some of the European OEM's saying that oil usage of 1 liter is normal in 1500 miles. Interestingly is that in America, the oil companies set the oil standards. In Europe, the OEM's set the oil standards. I also re-build the infamous Chrysler 2.7's with great success. These motors need synthetic to keep from sludging, (except for a great amount of cylinder head grinding), but the synthetic evaporates from them due to a hyperactive pvc system. The big plus in these motors is that the synthetic does not sludge when you get the eventual water-pump leak into the crank-case.