Originally Posted by finklejag
Most 0W-20 oils on the market have a starting Viscosity @100c between 8.0-8.7. The Amsoil OE 0W-20 has a starting viscosity 8.3.
With his oil having a Viscosity of 6.88 at the end of the oil change interval. It sheared down a little. It's still a 20 weight oil though. Most 5W-30's shear down to a 20 weight after a long oil change interval. But 5W-20's usually stay pretty much where they start. The car is breaking in, so that's why the Viscosity is where it's at.
i see the Amsoil OE and XL (I currently have XL in mine) start at 8.3, but the Signature series starts at 8.7. and is what I have been planning to run starting next fill.