Originally Posted By: dwendt44
Plenty of conventional 5W-20 oils out there.
Now 0w-20 USED to be synthetic only. Nowadays, there are blends that are 0W-20.
I wonder why Xw-20 is needed for proper operation of the multiple displacement as that's largely a computer operation, cutting off fuel and spark to four cylinders when manifold vacuum is high.
There are special lifters on the cylinders that are deactivated when MDS kicks on. The lifters have a pin that is moved via oil pressure which allows the lifter to collapse into itself and not be raised up by the cam lobe. There are solenoids that open upon a signal from the computer and allow the oil through special galleries to reach the lifters. That part of MDS all operates off oil pressure and flow and needs a 20 weight to properly activate and function. The fuel and spark part of it are computer controlled but there is a mechanical part to MDS that relies on oil to properly function.