Just got off the phone with Bill @ RLI (he's the VP) with some questions about their oils in VW 502/505-spec'd vehicles. I explained that the 502/505 list is heavy 30s and light 40s, ACEA A3/B4 meaning HTHS of 3.5 or better. My specific questions were how about how suitable he thought the 0w30, 5w30, and 5w40 was for this sort of application.
Bill said that they've recently reformulated the PCMOs with new and better polymers. He also explained how the additive packages were revised to meet API SN and ILSAC GF-5; this was done since auto manufacturers are starting to become more strict on oil formulations.
In particular, he told me that the 0w30 and 5w30 PCMOs offer HTHS of 3.6-3.7, and the 5w40 has HTHS of 4.3-4.5. There is a bit of variance here because their polymer suppliers also supply them with a range (Lubrizol was one company he mentioned).
The 0w30 relies on PAO for the low-temp performance, and the 5w40 relies on it for the wider viscosity spread. Bill actually told me that the Brookfield values for the 5w40 put it on-par with most 0w40s.
He made an interesting point about the HDEO 15w40 really being closer to a 5w40. They market it as a 15w40 because that's what the diesel manufacturers want, but again, the Brookfield values point to it being close to 5w40. Basically the 15w40 is like a 5w40, but has the shear stability of a 15w40.
I was really impressed with his candor and openness. He wasn't hiding anything and answered anything I threw his way. For my car, he said the 5w40 is the best choice if I'm out on the track (and because I have a very complex valvetrain). But he did say the 5w30 would definitely suffice too.
tl;dr: the 0w30 and 5w30 RLI PCMO has HTHS of 3.6-3.7.
Bill said that they've recently reformulated the PCMOs with new and better polymers. He also explained how the additive packages were revised to meet API SN and ILSAC GF-5; this was done since auto manufacturers are starting to become more strict on oil formulations.
In particular, he told me that the 0w30 and 5w30 PCMOs offer HTHS of 3.6-3.7, and the 5w40 has HTHS of 4.3-4.5. There is a bit of variance here because their polymer suppliers also supply them with a range (Lubrizol was one company he mentioned).
The 0w30 relies on PAO for the low-temp performance, and the 5w40 relies on it for the wider viscosity spread. Bill actually told me that the Brookfield values for the 5w40 put it on-par with most 0w40s.
He made an interesting point about the HDEO 15w40 really being closer to a 5w40. They market it as a 15w40 because that's what the diesel manufacturers want, but again, the Brookfield values point to it being close to 5w40. Basically the 15w40 is like a 5w40, but has the shear stability of a 15w40.
I was really impressed with his candor and openness. He wasn't hiding anything and answered anything I threw his way. For my car, he said the 5w40 is the best choice if I'm out on the track (and because I have a very complex valvetrain). But he did say the 5w30 would definitely suffice too.
tl;dr: the 0w30 and 5w30 RLI PCMO has HTHS of 3.6-3.7.