You guys should know this one. I emailed this question to Jonny the Pennzoil guy, but I haven't heard from him. I wonder if he's dropped off the face of the planet, or was he a victim of big oil hit men?
The specs for Pennzoil 5w-20 look very good on paper. The flash point and pour point seem very high for a "dino" oil. I would imagine that this would be evidence of using a superior base oil (group III and II+). The specs are below.
Flash Point 229C (445F)
Pour Point -45C (-49F)
Vis. @ 40C 48
Vis. @ 100C 8.6
Vis. Index 158
ASTM D-5293 HTHS 2.65
bottgers: Sorry I did not get right back to you. I only check this board about once per week now. I use to be like Patman but had to take drugs to calm me down.
Anyway, the answer to your question is yes. Give or take 5%
On the product data sheet the viscoscity shows 8.6@100 but when I sent a sample away to Blackstone it came back vis@100 8.1. Big difference from Pennzoil website.