MTF Comparisons?
Here's Pennzoil 's product data sheet for their Synchromax. It says it's made from paraffinic base stocks. So not synthetic, but with high lubricity. Compared to Valvoline, the cold viscosity is a little thinner and the hot viscosity is a little thicker. That's explained by the viscosity index number, which is quite a bit higher than Valvoline's. I must have been wrong in assuming there is some synthetic base oil in the Valvoline based on viscosity index. Simply put, the higher the viscosity index, the less a lube will thin when heated. I'd use the Pennzoil in any street application.
Here's Pennzoil 's product data sheet for their Synchromax. It says it's made from paraffinic base stocks. So not synthetic, but with high lubricity. Compared to Valvoline, the cold viscosity is a little thinner and the hot viscosity is a little thicker. That's explained by the viscosity index number, which is quite a bit higher than Valvoline's. I must have been wrong in assuming there is some synthetic base oil in the Valvoline based on viscosity index. Simply put, the higher the viscosity index, the less a lube will thin when heated. I'd use the Pennzoil in any street application.