First effort would be to remove and check your PCV valve. Shake it...if it doesn't rattle, clean it out with carb or intake cleaner. (No need to buy a new one.)
You might want to go to a slightly thicker oil. Try 5W-20 or even 5W-30 (even that weight should work well in Wisconsin, synth has good cold pouring properties). More info on BITOG than here!
Following the MM is fine, your usage is not severe, but JMHO a regular M1 oil would be just as good. I don't think that switching brands would make a significant difference, we use whatever synth is on sale/rebated, and have consistent oil usage over 185K miles.
You might want to go to a slightly thicker oil. Try 5W-20 or even 5W-30 (even that weight should work well in Wisconsin, synth has good cold pouring properties). More info on BITOG than here!
Following the MM is fine, your usage is not severe, but JMHO a regular M1 oil would be just as good. I don't think that switching brands would make a significant difference, we use whatever synth is on sale/rebated, and have consistent oil usage over 185K miles.
