In my last car I always ran what gm recommended. mobil 1 synth 5-30. However I know there are many opinions on oils and brands, and I'm not convinced the mobil is what I should use. I did some searching to no real avail on the subject here. Give me your thoughts and reasons for your choices...

After a WOT run I noticed some noise......clicking noise. I pulled over and noticed I was low on oil. I added a quart I had in the trunk and the car stopped making any noise. Next thing I noticed was that I had low oil pressure (6psi) at idle). Though no light came on, I was still concerned. My...