ZDDP Content

[GMBoy]

I have a few older classics, my oldest being a '32 Ford Model B. I have my own opinion of this topic and my own course of action unique to each of my vehicles. With that, and all due respect, I am refraining from giving my advice because I cannot back up with data/facts that what I am doing is the best option. I won't put enough miles on these cars to see any good/bad out of my oil diet.Yet, so many are here throwing out their ideas as if it's the best way to go period and i can find flaws in quite a few of these recommendations (but again who really is right?)!

With that - the best advice given here was to reach out and talk to the folks that care and preserve those old models as part of their regular jobs. Car museums , old car parts outfits etc - these are the one's with the knowledge.

 

[dave1251]

Originally Posted by sloinker
Just about any Group I or II monograde in your desired viscosity would be appropriate. It would be interesting to know how much zinc/phosphorous was in those early oils. I bet they had a high sulfur content and the oils were just basically straight strained crude tapped at the appropriate column height for viscosity.

There was none.

 

[dave1251]

Originally Posted by ARCOgraphite
From what I've read, with API SB came ~1000ppm ZddP

Wonder what the '37 Cord supercharged recommended?

Its a Beauty of a car.

I don't know where you read that fake news. Closer to API SF.

 

[DBMaster]

Originally Posted by ARCOgraphite
From what I've read, with API SB came ~1000ppm ZddP

Wonder what the '37 Cord supercharged recommended?

Its a Beauty of a car.

+1

 

[mpack88]

Wouldn't a model T originally running api SA? It would make me think it wouldn't need all that zddp.

 

[SpitFire6]

Ah, the internet world ...


Modern Oil has no zinc; I need zinc for my 2v 351M n my Country Squire! Yeah, yeah YEAH!

BOSE makes the best headphones ! Yeah Yeah yeah!

Chic-fil-A sandwiches are better than my Mammies! Ohhh Yeah!

Grupo Modelo Corona Extra is awesome Beer! Don't drink the water in Mexico though! Burrp!


Watch out for that dizzying 2500 rpm redline in that "A"

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API SB from the period allowed ~0.10% ZddP

So Get some 30ND from Autozone in the orange bottle and add your ZDP - UP of choice.

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Maybe give Valvoline a call, I bet they would be responsive.

I recall Jay Leno or somebody did an interview with an Ashland rep about a decade ago ....

Hi,
I have read that the sales of Corona have declined in the USA while sales in the GB have gone thru the roof.
Just saying.

 

[GMBoy]

STP Oil Treatment contains less ZDDP than modern API SN/SN+ oils so it will actually dilute the content, not add to it.

Also keep in mind that you can add too much ZDDP and actually increase wear due to toxicity. Another side effect of ZDDP is that it increases the coefficient of friction the higher the concentration. I like to see the least amount of ZDDP that'll get the job done for a particular application.

I also recommend using an oil that already contains the additive package that you need instead of using an aftermarket supplement with an unknown type of ZDDP. Additive clash from opposing chemistry can be a problem, especially with anti-foaming additives.

BEST advice right here. Buy a proper classic car motor oil which is properly formulated for the purpose and has the correct levels of ZDDP. You are guessing with additives and the STP has virtually none in the blue bottle and other additives may be too much ZDDP - we don't know. That is why a specialty oil is your best choice. I am sure you don't daily drive this car so the small additional costs is probably no concern.