I'm probably going to switch over from Delo to Amsoil in the crankcase however, I can't seem to find any hard data on the 15W-40 in comparison to the Series 3000 5W-30. Amsoil is very proud of the stats for the Series 3000 and reference test results in multiple places, but what about the 15w-40? I'm just wondering how good it is compared to the leading off the shelf stuff.
The weather here in Vegas doesn't exactly warrant the use of cold-flowing 5W-30

The weather here in Vegas doesn't exactly warrant the use of cold-flowing 5W-30
