Well, I went ahead and drained the Mobil 1 and took off the AC Delco filter. I put on a Purolator filter and dumped in Havoline convential oil. The expense of Mobil 1 couldn't be justified in my mind. Yes, I did my research and took the advice from the many folks on this site. Of all the convential oils I have run in all the cars I have owned Havoline flows faster, reduces start up knock and rattle quicker than any convential oil I have ever used. Too boot it does not have the burn off like other conventional oils like Valvoline, Pennzoil, Quaker State and not to mention Kendall which has been the worst as far as burn off is concerned. Would appreciate any and all comments.