The W = winter thing is a misnomer. Your ou can say it means winter if it helps you remember that its what the oil flows cold. Not just in winter. Before the W is what it flows cold. After the W is what it flows at operating temp. That simple.
Let's all remember. It's not necessarily cold when it's winter.
That's as much as I'll hijack this thread on oil and viscosity.
As for your oiling problem. It doesn't really sound like there is one. The heavier weight oil may be only slightly more pressure than a lower oil. If you're that worried about it. You could try running a 10W30. This is what I run and it's a good oil for our wild Alberta temperature swings. Bring it up to temp. See what your pushing then. You may be surprised. This will be the only way to see if there is a problem in my mind.
