I have an LS1 GTO and I currently run M1 5w30 with a quart of 15w50 and a ZDDP additive for protective overkill. The additive actually really quieted the lifter noise that these engines are famous for even new. The 15w50 was necessary to quell the mild consumption I was getting. I'm burning just under a quart every 4k miles without the 15w50. My reading around here is showing me the consumption seems to be common with 5w30 M1 and most likely isn't just a symptom of the motor and it's the only oil I have had consumption with. I've ran M1 0w40 and the lifters would get noisy again after 3k miles. I've also ran GC 0w30 and I have found it to be noisy as well. I'm sure in both of these cases ZDDP additive could help, but they already have elevated levels.
I think moly is going to be my answer to not "homebrewing" my own stuff. Mixing is annoying to say the least. I don't even mind thin 30w as my oil pressure is strong. On M1 5w30 I'm very close to 30psi at hot idle and I'm already past 60psi at 5k rpms. I prefer to buy oil in the 5qt jugs from Walmart because of the better value and I've noticed 10w30 Castrol Edge there lately. 5 qt jugs add a lot of convenience too because I also own a Jaguar S-Type 4.0 and I like to use the same oil in both cars. I've not had any of the same concerns of consumption in any noticeable level, nor do I have the noise with the overhead cam design.
Anyway as I've mentioned, I'm thinking of trying the Edge. Does anyone else have recommendations? At least with the Edge, I'm leaning towards 10w30 over the 5w30 being in a warmer climate and the VOAs seem to show the 10w30 is a bit thicker warm unlike M1 which shows the 5w30 thicker than their 10w30.
Sorry for the long post!
I think moly is going to be my answer to not "homebrewing" my own stuff. Mixing is annoying to say the least. I don't even mind thin 30w as my oil pressure is strong. On M1 5w30 I'm very close to 30psi at hot idle and I'm already past 60psi at 5k rpms. I prefer to buy oil in the 5qt jugs from Walmart because of the better value and I've noticed 10w30 Castrol Edge there lately. 5 qt jugs add a lot of convenience too because I also own a Jaguar S-Type 4.0 and I like to use the same oil in both cars. I've not had any of the same concerns of consumption in any noticeable level, nor do I have the noise with the overhead cam design.
Anyway as I've mentioned, I'm thinking of trying the Edge. Does anyone else have recommendations? At least with the Edge, I'm leaning towards 10w30 over the 5w30 being in a warmer climate and the VOAs seem to show the 10w30 is a bit thicker warm unlike M1 which shows the 5w30 thicker than their 10w30.
Sorry for the long post!