You guys that like 15W-50...here's what you need to do:
- Put a bottle in your frig and get it cooled off to 40-45 deg
- Pour some out in a small pan
- Note how well it flows (or lack thereof)
- That's what your oil pump is trying to get to your pistions and valves.
Basically you're increasing the wear on your motor...on each cold start. Now try the same thing with a 0W-30 or 5W-30...bet it flows better
The highest weight oil I would ever run is a 10W-40 and that on a high milage motor. You want the oil to flow so it can do it's job. The second number is the visc of the oil at temperature...30W is plenty for a fresh 7M motor. if you want to decrease the wear on your new engine, 0 to 10W-30 (depending on climate) is what you want.