Recent content by mechengineer60

Well we know 40 years ago Ferrari put a spec on the oil at 10W50. I think you have underplayed how much better the film strength is now than oil 40+ years ago and appear to be going with the line only viscosity matters and not the quality of the oil/film strength etc, if they(Ferrari) had...

Your logic seems to be its all about thickness of the oil/covering surface/viscosity that causes wear. But what we have today is thinner oils that have higher protection factors. Oil pressure is just a proxy for viscosity, it may well be that the ferrari could achieve the same standard of...

I take it you dont think that will be a good thing? Is your preference for gasoline powered ICE's?, ICE's can run on other fuels which wont cause fuel dilation: propane or propane/butane mix, hydrogen, but would still suffer from water condensation/dilution.

Interesting about direct injection and the oil dilution issue. We want to encourage people to burn less fossil fuels, drive their ICE less, but we are sold cars where we are told that normal use should be getting them to operating temp for at least 15 minutes per drive etc, that's a lot of...

"If you knew the typically shape of an oil's viscosity vs temperature curve" Id say I do know, and these curves displayed by a reputable oil supplier are typical of everything else out there: https://penriteoil.com.au/knowledge-centre/Viscosity/237/understanding-viscosities/181. You are...

"That is the graph" Two data points make a graph, ? for something we know isnt linear, well not in my world, but ok. even in your world if we join the two points for 40 and 100C with a straight line for both oils the 5W20 will show higher viscosity from -35 to 95 C, Id say its a thicker oil...

of course there is rounding.......we dont see numbers/specs ending in anything other than 5s or 0s, do you really think manufacturers are able to produce an oil that is exactly 5w or 0w? in regards to fuel consumption disagree, especially when the vehicle is driven in the cold state more often.

If an oil remains at a higher viscosity through the temp range its thicker, just comparing one temp and saying the other is 1/10 of centistoke thicker at one temp at the end of the range does not mean its a thicker oil As I said, show me a graph of any oil where they have the same 100C rating...

The data there does not disprove what I am saying and rather confirms it, though in the specs there is very little difference between those two oils, but that is only based on 3 data points, the most significant being -39 0W and -36 pour temp, 5W The whole graph of viscosity versus temp will be...

yes you could have variations between manufacturers because the first number is rounded to the nearest 5 and the second to the nearest 10, but all things being equal, the 5W rating is going to mean its thicker right through to the upper temp viscosity. Look at any graph of viscosity versus temp...

Show the viscosity graph of any 5W-20 versus a 0W-20 graph and tell us at what temp the viscosity of the latter is more than the former? it will be lower for all temps

basically the numbers represent the end of the temp range viscosities, meaning both oils have the same viscosity at ~100 C. but it can be guaranteed the 5W oil will remain thicker all the way from -30C up to that temp of 100 C, so its a thicker oil

no it does not thicken as it gets heated nor does the viscosity increase, its just the degree of thinning is reduced from what happens to a monograde oil.

Basically the manual says you can put a whole lot of different oils in there without risk of major damage or seizing the engine, but what is best? People here seem to underestimate the fuel usage issue. There is even a 5w30 and a 5w50 are going to have a huge difference in viscosities(with...