HTHS on Schaeffer Supreme


Staff member
Guelph, Ontario
When you look at the technical data on the 5w30 and 10w30 Supreme 7000 blends, they both show an impressive HTHS of 3.5, higher than many full synthetics. But at the same time, they also list a viscosity range of 10-12 cst at 100c. So if someone gets a batch which is formulated at 10cst (which my first case of 10w30 was) does that mean the HTHS would be lower? Or would the 10 cst batch have an HTHS of 3.5 and the thicker batches would be even higher?
Las Vegas, NV
I think that it would be reasonable to expect the the HT/HS numbers could be in a range of about 3.4 CP to 3.6 CP. The reason Schaeffer's puts a range for the viscosity at 40C and 100C might be because it would be easy to test that viscosity in a lab but it would be more difficult to determine the HT/HS values. You would not get the HT/HS in a normal UOA or VOA. I think that a thicker 10w-30 like Schaeffer's would be a good choice for a large displacement north american V8 engine.