Oil ratings, API classifications and oil integrity

[Kern Dog]

Today I stumbled upon a small stash of UNused oil in bottles that had no date code on them but did have the SAE API circle with ratings of SD and SF.
I thought that I was told that the higher in the alphabet the second letter was, the higher the detergent level.
In short, an oil like this:

...with it's SN rating is a MUCH higher detergent oil.
If this is true, what other characteristics could be said about this older oil? Is it possible that it may have a higher Zinc count as well?
I ask because I suspect that as the oil market adjusted to meet new car emission standards, they also included roller lifters that didn't need the cushion effect that was crucial for flat tappet engines.
I have 20 quarts on unopened "classic" oil that have either the API SD, SF or no rating at all. The oldest oil that I got is in cans!

I don't intend to use this in my red car. I use "Driven" oil simply because of the stiffer valvesprings and solid lifter cam.
I have a few other lower performance flat tappet cars out back that may benefit from an older formula of oil. They do all have softer valvesprings which probably saves the lifters and camshaft from excessive wear.
What say you? Do you think the lower detergent oil may carry a higher amount of Zinc/ZDDP ? How would it even be determined without an oil analysis?

 

[pnora]

Today I stumbled upon a small stash of UNused oil in bottles that had no date code on them but did have the SAE API circle with ratings of SD and SF.
I thought that I was told that the higher in the alphabet the second letter was, the higher the detergent level.
In short, an oil like this:

View attachment 1575278

View attachment 1575281

...with it's SN rating is a MUCH higher detergent oil.
If this is true, what other characteristics could be said about this older oil? Is it possible that it may have a higher Zinc count as well?
I ask because I suspect that as the oil market adjusted to meet new car emission standards, they also included roller lifters that didn't need the cushion effect that was crucial for flat tappet engines.
I have 20 quarts on unopened "classic" oil that have either the API SD, SF or no rating at all. The oldest oil that I got is in cans!

I don't intend to use this in my red car. I use "Driven" oil simply because of the stiffer valvesprings and solid lifter cam.
I have a few other lower performance flat tappet cars out back that may benefit from an older formula of oil. They do all have softer valvesprings which probably saves the lifters and camshaft from excessive wear.
What say you? Do you think the lower detergent oil may carry a higher amount of Zinc/ZDDP ? How would it even be determined without an oil ana Oil Categories

Oil Categories

 

[69L48Z27]

CH4 or CK4 are the ones I’ve always been told carry Zinc.

 

[Kern Dog]

Oil Categories

I'm interested in what differences there are between SD and SF.
Catalytic converters became common in 1976 and later engines so I wonder if the SD and SE formulas were changing for that?

 

[Kern Dog]

I made an error. Almost half of the oil is SG rated.

Check these out… if nothing else, they’d be garage art.

 

[70bigblockdodge]

Anything beyond SG is garbage for older cars

 

[moparedtn]

Anything beyond SG is garbage for older cars

In a word - correct.
SH designation signaled the beginning of removal of zinc and phosphorus from motor oils (around 1991).

 

[1 Wild R/T]

I thought you said oil.... Pennzoil isn't oil....

 

[pnora]

I made an error. Almost half of the oil is SG rated.

View attachment 1575373

View attachment 1575374

Check these out… if nothing else, they’d be garage art.

View attachment 1575375

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View attachment 1575377

I would imagine emissions play a lot into it. Then you have to consider what API is. It is an assurance that the oil meets a certain standard. A lot has to do with what the car manufacturers are requiring. Every couple of years the bar is raised and the oils need to meet the requirements. Lots out there to read on is one is bored.

 

[pnora]

In a word - correct.
SH designation signaled the beginning of removal of zinc and phosphorus from motor oils (around 1991).

If that was true todays oils are junk. There was more zinc in the older oils.

 

[Kern Dog]

I thought you said oil.... Pennzoil isn't oil....

There are 9 quarts of this too:

 

[1 Wild R/T]

There are 9 quarts of this too:

View attachment 1575454

View attachment 1575455

Now you've struck oil....

 

[moparedtn]

If that was true todays oils are junk. There was more zinc in the older oils.

*sigh* That's what I said...
Let me try this again for you - oil produced prior to 1991 and the onset of the SH oils had zinc and phosphorus
in it:

By federal mandate, the arrival of the SH classification spelled the end of zinc and phosphorus...both of which are
detrimental to emission control systems on modern cars.

As far as "today's oils are junk" - no, but they don't do our older engines any favors, as they need zinc and phosphorus
for several reasons.

 

[pnora]

*sigh* That's what I said...
Let me try this again for you - oil produced prior to 1991 and the onset of the SH oils had zinc and phosphorus
in it:
View attachment 1575489
By federal mandate, the arrival of the SH classification spelled the end of zinc and phosphorus...both of which are
detrimental to emission control systems on modern cars.

As far as "today's oils are junk" - no, but they don't do our older engines any favors, as they need zinc and phosphorus
for several reasons.

*****sigh**** I thought you meant the opposite. Sorry for wasting your time.

 

[Kern Dog]

*sigh* That's what I said...
Let me try this again for you - oil produced prior to 1991 and the onset of the SH oils had zinc and phosphorus
in it:
View attachment 1575489
By federal mandate, the arrival of the SH classification spelled the end of zinc and phosphorus...both of which are
detrimental to emission control systems on modern cars.

As far as "today's oils are junk" - no, but they don't do our older engines any favors, as they need zinc and phosphorus
for several reasons.

THIS was what I was after.
The part where you wrote "By Federal mandate, the arrival of SH spelled the end....."
THAT was what I suspected. It was because of that, that I suspected that this old oil could be better to use than the newer stuff in a flat tappet classic.
I didn't stumble into a dormant refinery...I only got 9 quarts of the Pennzoil and 9 of the Castrol, plus a few "cans" of stuff made before the API system was used.

 

[1 Wild R/T]

FWIW the cans started getting phased out around 86.....

 

[RemCharger]

Part of the newer fancy oils ( vw bmw Japanese etc) formulation is to deal with the higher heats they run at. And subsequently, longer drain intervals and sludge.

Change your oil frequently and use what you want.

 

[4speed68rt]

Where did you find them?

 

[Photon440]

THIS was what I was after.
The part where you wrote "By Federal mandate, the arrival of SH spelled the end....."
THAT was what I suspected. It was because of that, that I suspected that this old oil could be better to use than the newer stuff in a flat tappet classic.
I didn't stumble into a dormant refinery...I only got 9 quarts of the Pennzoil and 9 of the Castrol, plus a few "cans" of stuff made before the API system was used.

AMSOIL Z-ROD high zinc oil is rated for SL and lower designations.

 

[Kern Dog]

Where did you find them?

I went to the county dump to dispose of some used oil and a dead microwave. They have a section where they give away unused "hazardous waste" stuff like oil, ATF, brake fluid, anti-freeze, household cleaners, spray lubricants...all sorts of stuff.