Originally Posted By: 02s4audi
I have been looking into royal purple and noticed that back a few years people really complained of shearing in turbo applications. What about now? Is it fixed? What about the hps formula?
Originally Posted By: 02s4audi
If I run PP it will be the euro 5w-40 formula which I can only find at autozone for $9 a quart.
Just so you are aware RP HPS is not offered in 5W40. 5W40 is only offered in their API line. FWIW it is API SM as well and not SN like most of the other weights. It isn't going to have the high ZDDP additive level the HPS line will( unless that weight has some kind of different ppm standards for ZDDP @ the SM level than other weights? ).
Also, you can get it online for less than what you quoted locally. For instance, Jegs sells it for $7.86 p/qt and if you buy at least 4 qts the shipping and handling are free. I found it on Ebay for $7.49 p/qt with free shipping as well. I don't have time to search for a better deal for you right now but those 2 places yielded much better prices for you with little effort. Jegs especially ships super fast. When I order something from them I usually have it within 2-3 days.
As far as the "RP Shearing" thing. That is OLD news and it dates back to the old SL formula in 5W30 weight for the most part. Even then it was vastly overblown by the anti RP folks. One or two incidents became an indictment of the entire product line. No one can tell you if the API 5W40 will shear based on that.
I would say it would be no more likely to shear than any off the shelf name brand 5W40 you might try from Mobil 1, Pennzoil, Castrol, etc... If you want to give it a try do so. It should do the job well. However, if you have any concerns just have a UOA done and see how it holds up and then you will know.