Originally Posted by Gokhan
I have updated my spreadsheet for the Shell AV-L 5W-30 and Shell AV-L 0W-30, both VW 504.00.
As you can see, 0W-30 has more viscosity-index improver (VII) polymer, which will increase the turbocharger and intake-valve deposits (IVD). It also has a thinner base oil, which will increase the engine wear. I assumed HTHS = 3.5 cP for both; however, chances are that for the 5W-30 it is a little higher, which will make the real discrepancy for the VII content and base-oil viscosity between the two oils even more.
Estimated VII content and base-oil viscosity (BO DV150) of selected oils
As far as IVD between 0W30 and 5W30, i leave it to experts to discuss but I think you are making it sound worst than it is considering that 0W oils have a much better base oil and a higher natural vi ... but let's forget about that for now because that may get very technical and over my head
However, you are also saying that the thinner base oil in 0W30 (as oppose to 5W30) "will increase the engine wear" ...
imho and assuming that 0W30 will have a thinner base oil, the increased engine wear if any should be VERY insignificant and/or minimal to even be mentioned as a deciding factor or otherwise ... and it is borderline misleading. We are talking about two x30 oils. At the same time and in other threads, you highly recommend xW20's.
Again this is based on what I've learned on bitog. Please explain and/or elaborate if I'm wrong!
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