Mobil 1 Classic 10w30 (High-Zinc Formula)

That would be the phosphorous, though it's clear that the marketeers at Mobil know that Joe Average associates ZDDP with "Zinc" and not the actual anti-wear part of the compound: phosphorous, or they'd be putting "high phosphorous formula" on the label.
Agreed, but I'll add that it isn't just Mobil's marketing team that's keen. Castrol marketed high zinc for GTX Classic, as does Valvoline with VR1.
 
To me, GTX Classic was a cool product that was offered in the wrong viscosity. It was only available in 20W-50 which I think was a mistake and likely the biggest reason why it isn't around anymore.

It's still available, just not at Walmart. You can get it on Amazon (from Castrol/Amazon itself, not some unknown re-seller) and also at Autozone (1 qt bottles only at AZ) .
 
The year range makes no sense to me. I would have to guess cars older than 1951 would also do fine with this oil, and I am surprised it goes all of the way to '96, since I thought oils like this shouldn't be used with cat converters.

Any one have any opinions on how this stuff compares to Valvoline VR1?

API SJ, released in '96 reduced ZDDP to 1000ppm. This was the first time oil ratings reduced zinc/phosphorus. Previously, the levels were at 1200 ppm or so.
 
API SJ, released in '96 reduced ZDDP to 1000ppm. This was the first time oil ratings reduced zinc/phosphorus. Previously, the levels were at 1200 ppm or so.
Yes, that's correct, phosphorous was restricted to 1,000ppm (there's no restriction on zinc) starting with SJ, it was 1,200ppm under SH. This was reduced to 800ppm with SM. No limit applies to xW-40 and above grades.
 
Agreed, but I'll add that it isn't just Mobil's marketing team that's keen. Castrol marketed high zinc for GTX Classic, as does Valvoline with VR1.
And on the other side you’ve got stuff like Castrol Edge 5w-50 that has equally high zinc/phosporus levels but doesn’t make any mention of it.
 
I would not use the price as an indicator of performance. Case in point: there are patent results on racing oils by Shell where VR1 outperformed Redline racing oil (most expensive) and Mobil 1 Racing (also expensive). This was posted by buster eons ago. https://bobistheoilguy.com/forums/threads/shell-racing-oil-patent.106641/
Manufacturers choose the price they think will provide them with the most profit.
 
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I'm curious, what's the significance of 1951? That would sort of exclude my Lincoln for some reason.
From the crash course I just took via Google, it seems that's appx the time that full-flow filters and detergent oils became standard(ish) equipment. They're probably trying to un-liable themselves from being held responsible if someone starts running this in an original earlier unrebuilt motor and clogging the oil pump pickup.

Again, this is from the 10 minute dive I just took around various antique auto/tractor forums discussing oils and specifically detergent vs non-detergent oil usage. Feel free to Google it and do your own exploration into the topic.
 

Applications

• Mobil 1 Classic is for engines with flathead or overhead valve designs
Mobil 1 Classic is specifically not for overhead cam (modern) engine designs

Hmm, what can possibly make this oil "not suitable" for OHC engines? That's where the high Zn/P additive protection is needed the most... on the overhead cam lobes of high-revving, high stress OHC engines with VTEC/VVTL-i like my 2ZZ-GE. My guess is the marketing dept forced that statement in there to prevent people from pouring this oil into GDI engines and getting sued for causing LSPI.
 

Applications

• Mobil 1 Classic is for engines with flathead or overhead valve designs
Mobil 1 Classic is specifically not for overhead cam (modern) engine designs

Hmm, what can possibly make this oil "not suitable" for OHC engines? That's where the high Zn/P additive protection is needed the most... on the overhead cam lobes of high-revving, high stress OHC engines with VTEC/VVTL-i like my 2ZZ-GE. My guess is the marketing dept forced that statement in there to prevent people from pouring this oil into GDI engines and getting sued for causing LSPI.
it's just because it doesn't have a modern API approval.
 
Good move Mobil 1. Now make it available in 5 quart jugs at Walmart. I recently saw VR1 conventional 10W-30 in 5 quart jugs at Walmart for $26. Before that I only saw 20W-50 quarts in parts stores. What I really want is VR1 10W-30 synthetic in 5 quart jugs at Walmart price.
 
there are other high zinc oils (if really needed) out there to choose from, consider some Euro oils like Pennzoil 5w-30 euro,,Walmart may still have it, would be a fine choice.
 
Clearly there's enough demand to make it worthwhile to offer this stuff.
KInda sad, as it's the total opposite of the EV regime (keeping older vehicles on the road).
What's sad about keeping older vehicles on the road? Far more energy and resources go into building new cars in general than what goes into keeping a good running older vehicle on the road. Keeping what's already built in useable condition is far more "green" than building/buying a new car.
 
Interesting product, but considering Mobil already offers several high zddp oils I have to wonder why. What is the viscosity at 100 degrees Celsius on this oil? ESP 0w30, while being a low zddp oil, is practically a 40 grade. Not saying it isn't a good product just wondering if they'll actually sell it or if this will end up being the next clearance oil at AZ.

OTOH it's always nice to see another option for flat tappet cam applications. Wonder if they're take the same approach as they do with the 15w50, which is API SP additive package but with higher zddp?
 
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