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EOS GM additive

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I've got a Porsche 930 as well as the TR. The Porsche club guys,(those guys are like Freak'in Scientist) use an entire bottle (16oz) of EOS in the Porsche motor. The 930 motor holds about 13 quarts if oil.

So that means they use a little more than 1 oz of EOS to each Quart of motor oil.

With that, I'd figure you could probably double the amount of EOS you're using.

The problem now is that GM has discontinued thier EOS.

There is another EOS that is still available from AC Delco. I just have'nt heard wether or not the AC Delco stuff is the same as the GM stuff.
 
I tried to get some EOS a few weeks ago and also found that it's been discontinued so I used red bottle (4cylinder) of STP Oil Additive. STP has ZDP in it and I understand that the red bottle's contents is not as thick as the blue bottle's contents and also contains more ZDP.
Not everyone carries it, but did locate it at Kragen's (Pep Boy's and Autozoe don't stock it).
Bob
 
I purchased a case of EOS last year from https://www.gmpartsdirect.com - Old GM EOS p/n 1052367

And now their web site states:

"Gm has reinstated this EOS and the new number is 88862586. Currently it is not yet available but will be soon! Please email us before ordering to insure we can supply you!"

And there's also Valvoline Synpower Oil Treatment - bought a 6-pack from a guy off ebay so I have enough zinc for my lifetime at least! See this thread https://theoildrop.server101.com/forums/showflat.php?Cat=0&Number=473586&an=0&page=3
 
I bought some AC DElco EOS from my local GM dealer in June. The clerk asked if I had a 4 cylinder or a 6 cylinder engine. So I bought the smaller container for a 4-cyl engine. I drove 3200 miles after the re-build and then changed the oil. I bought another small bottle (about $7.00) and added it with the oil. They never talked about any changes. But I'm in Canada and maybe things are different here.

Hey ! I know they are different !
 
What is EOS ?
 
AC Delco EOS from your local GM dealer is a supplement (Delco refuse to call it an additive) that contains sufficient amounts of zinc (ZPPD) which is essential after you rebuild your TR engine (flat tappet engine) if you have changed the camshaft or had it re-ground.

Google ZDDP (Zinc dialkyl dithio phosphate) as well as ZDDP tappets, etc
 
Or run yamaha motorcycle oil. Still not depleted. What I use, works fine.
 
For what's it worth both the AC Delco bottle and the GM bottle read the same as far as the label is concerned. Neither is recommended as an oil additive,...although that's what most people use it for.

I'm sure thier recomendation to not use it as an additive is Exhaust Emission related.
 
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