Update to my last thread. After a round of M1 5w30 and one of GC 0w30 (made in Belgium, actually), consumption is pretty close. After analyzing my oil tracking log, it seems to drink a couple of quarts between OCIs, about 1qt / 1500 miles (I recalculated the numbers from my previous OC, which I believe I had originally done incorrectly in that thread). So at least it hasn't gone up :| Been doing some looking up, looking around. Couple of things occurred to me... Right from the owner's manual: "Infiniti recommends mineral based oils"... by mineral, I assume they're referring to dino. Maybe that recommendation is based on the syns available at the time. I don't know, what were syns like in 2004? I imagine not as advanced as they are 13 years later. Also came across this interesting / concerning tidbit:
Maybe it's complete speculation (I sure hope so!), but it's enough to make me think. Although, don't BMW/Merc/ze Germans recommend this specific grade for a number of their models? In any case, I gotta try something else. As much as I like having the extra protection of a good syn, especially because I like to drive hard, I can't help but think that using up *any* oil good for the engine, despite topping it up religiously. I don't know. Kinda back to square one here. I'm stuck between trying a high quality dino, a high milage full syn, a high mileage blend, or something with a 40 at the end.
The idea behind 0W is that, after any engine sits for awhile, all the oil has drained down to the pan, and there's not much protecting the metal parts of the engine ... I understand about oil draining back to the crankcase over time and that the '0W' would pump up quicker on startup, but I'm not surprised to here that bearings can be damaged thru it's use cuz b4 startup it's ALL drained back and there's nothing left 'sticking' to the bearings. Whereas there would be with a '5W' or '10W'. You gotta have something left 'sticking' or it's metal on metal on startup.