Long lasting question of what synthetics are true group iv or v synthetics. I have used Mobil 1 EP for a long time, and am still trying to figure out if its a true group iv syn. SO in the meantime of waiting for mobil to return my email, I emailed royal purple and this is what they sent me

"Antonio, We do not disclose the proprietary formulation of the RP Motor Oils but for those who feel they need to know - RP uses synthetic base stocks of Group IV and Group V but the diluents would be of a hydrocarbon base stock - Cheers and thanks for considering RP.

David

Royal Purple Inc
David Canitz
1 Royal Purple Lane
Porter, TX 77365"

Happy they sent me an email so quick. I was wondering for all you oil guys, what does this last part "but the diluents would be of a hydrocarbon base stock " mean?
THe response mentions that it is from group iv and v, so I would think ok they are really synthetic, but the last part I am not sure what this means, if they are watering it down with some group III stuff. Anyone? Bueller? Bueller? (sorry just saw ferris buellers day off this morning)

 

Group IV and V are full true syn base stocks.
IV = Poly-Alpha-Olefin or PAO.
V = esters.

Most additives are still diluted with group III (dino) oil so that is why there is still a bit dino oil present in full syn oils.
Never more then 5 % or so IIRC.

 

So this means that RP is a true syn as opposed to the group III myth about other oils?? and even the true syn's still use additives that arent syn???

I would think a company should just use pure IV or V, would be simplier in my mind, but then again I am no where near as god as Bob the oil guy. I just wanted to find a good real syn for my car, was between M1, RP and amsoil. I have used M1 in car for a long time, and developed a few leaks, but to be fair car had higher mileage.

 

I use royal purple because it is a full synthetic, and it also is very accessible. You can find it at a lot of places which is nice. Amsoil is good too, but there isnt anybody up here in Alaska who sells it within any reasonable distance of me, so my car gets royal purple. PLus i find it is easier to check the oil level with the royal purple since it is purple. Lol.

-Ian

 

The hydrocarbon based diluents are thinning agents and are necessary because synthetic base oils are too thick. The hydrocarbons are likely hydrocracked or hydroisomerized to the point where they are very consitent with PAO or ester based synthetic.

 

So this is for sure a true synthetic? i take it, since mobil 1 will not say anything about what group it is from, from the numerous emails I sent.

 

I won't use royal purple because I haven't seen one exceptional UOA, on the other hand I have seen more than a few very good amsoil and mobil 1(10w30) UOAs. I plan on using pennzoil platinum or amsoil as I haven't seen one of them show anything but minimal wear in every engine. I'm not bashing Royal Purple by any means, just voicing what I've seen in relation to others experience.

 

I don't think there is a true definition of "synthetic". Hydrocracked mineral oil bears little resemblance to traditional mineral oils. Applying 70 atmospheres of pressure and 750 degrees of heat changes its form substantially. It's not as if the 5% mineral oil composition is straight from the well to the bottle.

 

From what i heard Royal purple oil breaks down very fast. Greddy also reccomend not to use Royal purple oil with there turbos.

 

I was planning to continue to use mobil 1 10w30 ep, however the emals I get, never ever will say if they use group IV or V, I have point blank asked them 3 times in the last month, every time, they come back, with proprietary formula. Ive even mentioned case law where they can at least just tell the group its from and still nothing. I am assuming their lack of willingness to answer the question really does answer it, it must not be group iv or v, they may be pulling a castrol switch with group III. Pretty bummed, I really trusted mobil 1 brand, but now I guess theres only RP, Amsoil, and german castrol.