Originally Posted by TiredTrucker
How is it then that many folks use a 5w30 at sub zero temps with no issues? I have never used a 0wXX oil in my 50 years of driving and every year deal with periods of -20F or less on occasion. And 5w30 has done just fine. The stuff is rated for -30C / -23F in terms of CCS viscosity and most of the synthetic varieties have pour points 10 degrees or more lower.
That's all true, but remember that we're not comparing oils that are in direct competition here. As you should be aware, the Castrol 0w-30 in question can very likely be used in diesel engines up to and including those requiring a CI-4 (if not later). It has all the Euro specs. At one time, it was one of the few A3/B4 type lubricants available in North America, and there were times when there simply wasn't a 5w-30 equivalent. Castrol's own 5w-30 A3/B4 equivalent is certainly not a superior lube to their 0w-30 by price or other numbers.
The 5w-30 ILSAC, which was part of the original post, is not in anything resembling direct competition with their 0w-30 A3/B4. People aren't choosing (or shouldn't be) Castrol 0w-30 A3/B4 just because they see a low number before the "w" and a 30 at the end. Most are choosing it because it's an approved oil for a number of European applications and technically out of spec for many Japanese and North American applications.
How is it then that many folks use a 5w30 at sub zero temps with no issues? I have never used a 0wXX oil in my 50 years of driving and every year deal with periods of -20F or less on occasion. And 5w30 has done just fine. The stuff is rated for -30C / -23F in terms of CCS viscosity and most of the synthetic varieties have pour points 10 degrees or more lower.
That's all true, but remember that we're not comparing oils that are in direct competition here. As you should be aware, the Castrol 0w-30 in question can very likely be used in diesel engines up to and including those requiring a CI-4 (if not later). It has all the Euro specs. At one time, it was one of the few A3/B4 type lubricants available in North America, and there were times when there simply wasn't a 5w-30 equivalent. Castrol's own 5w-30 A3/B4 equivalent is certainly not a superior lube to their 0w-30 by price or other numbers.
The 5w-30 ILSAC, which was part of the original post, is not in anything resembling direct competition with their 0w-30 A3/B4. People aren't choosing (or shouldn't be) Castrol 0w-30 A3/B4 just because they see a low number before the "w" and a 30 at the end. Most are choosing it because it's an approved oil for a number of European applications and technically out of spec for many Japanese and North American applications.
