Originally Posted By: BMWTurboDzl
Shearing of M1 should be irrelevant being that hths remains unchanged. Thee is simply no reason to us a 15w oil in the m54/52. It subjective at best.
I've never seen a UOA which re-tests HTHS - have you? All I know is that I put in a ~14.0 cSt oil and took out an 11.x cSt oil 6,000km later with no fuel, coolant or water present. If I wanted to run a 30, I'd run a 30. GC which only starts at 12.1 cSt finished thicker than M1 0W40 did and the M1 started significantly thicker.
It's a great oil, but it DOES shear. I'm not sure why it has such a fanboy defense where people continually argue that it "doesn't matter".
On the 15W issue, that's what you get from a 40 weight, dino HDEO. It's not a "feature" that I'm pushing, that's just what they typically are. It is too thick for non-summer weather, unless in a southern clime. As I've already said, my M52 owner's manual recommends 15W40 unless it's so cold that the engine won't start around -18C. Whenever I have run a 15W40 in the summer, I take it out when temps are consistently close to freezing and I've been going back to GC for the winter.
Provided the ambient temperatures are appropriate, there's also nothing wrong with running a 15W40 in an M50/M52/M54/M62.
I'm now running T6 and hoping for all of the properties I love about T but with a cold viscosity more suited to year round use in my climate.
Shearing of M1 should be irrelevant being that hths remains unchanged. Thee is simply no reason to us a 15w oil in the m54/52. It subjective at best.
I've never seen a UOA which re-tests HTHS - have you? All I know is that I put in a ~14.0 cSt oil and took out an 11.x cSt oil 6,000km later with no fuel, coolant or water present. If I wanted to run a 30, I'd run a 30. GC which only starts at 12.1 cSt finished thicker than M1 0W40 did and the M1 started significantly thicker.
It's a great oil, but it DOES shear. I'm not sure why it has such a fanboy defense where people continually argue that it "doesn't matter".
On the 15W issue, that's what you get from a 40 weight, dino HDEO. It's not a "feature" that I'm pushing, that's just what they typically are. It is too thick for non-summer weather, unless in a southern clime. As I've already said, my M52 owner's manual recommends 15W40 unless it's so cold that the engine won't start around -18C. Whenever I have run a 15W40 in the summer, I take it out when temps are consistently close to freezing and I've been going back to GC for the winter.
Provided the ambient temperatures are appropriate, there's also nothing wrong with running a 15W40 in an M50/M52/M54/M62.
I'm now running T6 and hoping for all of the properties I love about T but with a cold viscosity more suited to year round use in my climate.
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