Any further info regarding the viscosity loss in the HPS 5w30 sample?
Is there an update on the RP HPS 5w30 ?
Any further info regarding the viscosity loss in the HPS 5w30 sample?
Is there an update on the RP HPS 5w30 ?
I'm not implying this is what you are saying, but it is unfortunately a very prevalent assumption in oil analysis circles these days.
Assuming shearing is responsible for any and all drops in viscosity is just not accurate.
I'll check with my supervisor Chris and see if he'll weigh in when he get's a chance.
RP has not been very forthcoming with specifications of their new base and HPS line of engine lubricants. The last time I checked the site, specs were still not public posted.
I'm subscribing to this thread, as I also believe that the formulation did shear rapidly, as no form of fuel dilution is present in this sample. Here is what I need to make an informed decision about this UOA.
Jimmy, what is the virgin cSt @ 100*C of Royal Purple HPS 5W-30? Since the website isn't listing any specifications, I need you to disclose it (if possible). I agree that shearing isn't always the reason why a lubricant decreases in viscosity. Fuel dilution also plays a vital role in this. However, in this instance, it appears this isn't the case.
The only VOA of any HPS oil I could find was of the 10w30, which had a cSt@100*C of 11.3
Royal Purple 10W30 HPS - Bob Is The Oil Guy
If the 5w30 has a starting cSt@100*C close to this, dropping to 8.5 cSt after just 4k miles, with little fuel dilution, is some serious viscosity loss.
We just did another oil change in the car. It's probably going to be a little while before I send in the sample though.
Any updates?
????? I gots to know.