Cutting GC

[Phishin]

I'm just having fun, playing around. Believe me, I can't wait to buy a new car or truck and keep top tier synthetic oil in it. No additives, just oil. Babied and spoiled forever.

Besides, show me an engine that failed because mixed oils were incompatible.

 

[Phishin]

Originally Posted By: GMorg
I seem to recall that Terry Dyson once wrote of GC and RedLine as a particularly bad witch's brew. However, I cannot find the thread to link here. It made a sufficient impression on me that I have not since mixed Redline and GC. My memory gets a little less reliable every year. So, take my comments as hear-say at best.


Not the original post, but it's mentioned here...
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=884652

 

[CATERHAM]

Originally Posted By: JimPghPA
BTW, the final oil viscosity of a mix is not a linear average of the oils used to make the mix, but it does end up being something between the thickest, and the thinnest, and is is weighed in the direction of the linear average. Such as if you put 4 quarts of 10W with 1 quart of 30W the final would be thicker than 10W and thinner than 30W, and closer to the 10W than it would be to the 30W.

That's why it's always best to mix 0W-XX oils with other 0W-XX oils, 5W-XX with 5W-XX etc if you are concerned about retaining your XW rating. But at non extreme temp's using a viscosity calculator works quite well. Ultimately it helps to have an oil pressure gauge to judge the operational viscosity affect of any
mix.

 

[GMorg]

I had forgotten about my 5wt mixing days. I also used 5wt Redline in Belgium Castrol. The original thread that is referenced in the Phisin link above is listed below:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=844325&page=3

 

[beanoil]

I stay inside the family, and am running 4 quarts of GC and 2 of Castrol Tri-Shield 5w20 in a 6 quart sump. But I will admit I have no definite data except to say the engine is very smooth, oil temp and pressure is similar to a conventional 5w30 (VWB) and nothing has blown up yet.

 

[Phishin]

Thanks for all the input.

Right now, I'm taking Valvoline bulk 5w30 fortified with extra zinc, moly, and esters out to at least 6k miles. Then I'm doing a COA to look at the numbers. To get a baseline on what my wear is at using my own mix. I'd never use just bulk 5w30, so this would be my baseline since I'd always spike the bulk 5w30 with additives.

Then I'll try GC. Maybe just straight GC.

Then maybe a M1 0w40/0w20 mix.

 

[dubie2003]

To avoid any issues with different add-packs, I'd mix it with another castrol product, probably Syntec to keep it a syn.

SideNote: Yes, I understand that all motor oils today and designed to allow mixing without clashing. Yes, I know that a syn today is not the same as a syn from before nor a German made syn.

 

[Phishin]

Sorry to bring this back from the dead....but I have a ton of Amazon points to blow (from their Visa purchase reward points) and some Amazon gift cards....so I was gonna order some oil, naturally!!

I have 24 quarts of GC in my stash as of now, as a result of the AAP BOGO deal. I still think I'd like to thin this oil a bit for my Nissan.

Since GC is mostly PAO, why not use a PAO based oil to thin it a bit? I was thinking Royal Purple 0w20. Or is there preferrance to cutting the GC with something like Mazda's 0w20, which is obviously a GroupIII+.

I know the Mazda oil will give me better VI's....this GC is going in for Summer use. I don't really care about VI's with this GC.

Thanks in advance.

 

[KCJeep]

I wouldn't pollute GC with anything else. JMO. But if you go that route I'd definitely stay with as much PAO as possible.