Originally Posted By: danielLD
KL31, I'm going to venture not one of those UOA is a either a Dyson Analysis or a Lucas Dynamics, eh?
IF you have an oil that has a high viscosity index(oil's ability to stay in grade as temp rises) then you don't need to go to a thicker weight. Here's the problem, the off the shelves formulas aren't suited for the cars that are pushed more, so people go to thicker weights because it ends up where they want it to be AFTER it's diluted and sheared. Those oils don't hold up under your kind of usage so of course, going to a 40 weight works. But it's a band-aid for what is really happening.
Interesting because Terry Dyson recommended 5w40 for both my 2.0 WRX and my 3.0 H6 Outback
KL31, I'm going to venture not one of those UOA is a either a Dyson Analysis or a Lucas Dynamics, eh?
IF you have an oil that has a high viscosity index(oil's ability to stay in grade as temp rises) then you don't need to go to a thicker weight. Here's the problem, the off the shelves formulas aren't suited for the cars that are pushed more, so people go to thicker weights because it ends up where they want it to be AFTER it's diluted and sheared. Those oils don't hold up under your kind of usage so of course, going to a 40 weight works. But it's a band-aid for what is really happening.
Interesting because Terry Dyson recommended 5w40 for both my 2.0 WRX and my 3.0 H6 Outback