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EOS

Kid_Again

Well-known member
Joined
Jul 6, 2004
Messages
1,171
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NJ - Which exit you from?
Corvette
65 SB Roadster, 66 BB Coupe
Engine Oil Supplement

...one of my buddies is WAY over the top concerned about the lack of zinc and phosphorus in the new SL/SM rated oils...he now says that he "knows" that EOS has had those additives removed....does anybody have documentation of what's in the current EOS formulation?

...i've sent an email to GM Powertrain but God knows if they ever get to answer that kind of question

...most of what i've heard is EPA bashing, i'm not fan of BIG GOVERNMENT but i would appreciate being pointed in the right direction....seems like some guy making something called ZDDP is making a fortune right now selling what amounts to an additive for an additive...reminds me of the tetra ethyl lead scare of a few years ago...yeah, i know, R-12 refrigerant is banned also and tell me you can't buy this stuff with no trouble at all :eyerole


GOD FORBID that they stop making muffler bearings:W
 
Engine Oil Supplement

...one of my buddies is WAY over the top concerned about the lack of zinc and phosphorus in the new SL/SM rated oils...he now says that he "knows" that EOS has had those additives removed....does anybody have documentation of what's in the current EOS formulation?

...i've sent an email to GM Powertrain but God knows if they ever get to answer that kind of question

...most of what i've heard is EPA bashing, i'm not fan of BIG GOVERNMENT but i would appreciate being pointed in the right direction....seems like some guy making something called ZDDP is making a fortune right now selling what amounts to an additive for an additive...reminds me of the tetra ethyl lead scare of a few years ago...yeah, i know, R-12 refrigerant is banned also and tell me you can't buy this stuff with no trouble at all :eyerole


GOD FORBID that they stop making muffler bearings:W
just break in the cam using "joe gibbs" motor oil made for cam shaft break in
 
ah, i see...zddp is zinc dialkyl dithio phosphate, the zinc-phosphate complex

i was just on the zddp website and my reading casues me some concern...

EOS has half the zddp level of EOS - So what?

EOS is designed for break-in only - OK, I'll check the label


...i'm beginning to see a money trail here;squint:
 
thanks motorman but i seem to be fixed on figuring out the facts about zddp


i checked the API wesite and SL oil does have zddp (i think one half the amount it used to) and the conventional wisdom is that EOS also has one-half the previous amount..

what is tough to find is what concentration of zddp is required to ensure the longevity of a solid lifter cam....i must admit that i replaced my solid lifter cam with an identical profile hydraulic cam because i thought it "sounded funny"...no change in performance but i swapped it out anyway and there was absolutely no problem with wear none just me being nervous again

i think somebody's just ripping off joe sixpack (a process also called Marketing)
 
what is tough to find is what concentration of zddp is required to ensure the longevity of a solid lifter cam..

If you use a CJ-4 or CI-4 API-rated diesel oil, it contains a minumum of 1200ppm (0.12%) of ZDDP, and that's more than adequate to protect the sliding valvetrain components in a flat-tappet street engine, without any extra additives. If you have a really radical cam and Gonzo aftermarket valve springs, that's a different story. :)
 
Do not use GM Engine Oil Supplement on a regular basis.

The current product is NOT the EOS from the 70s and 80.s It is only intended for break-in use and is not designed for continuous use as a pour-in additive or supplement.

The ZDP content is not an issue in any roller cam engine.

If the engine is a flat-tappet engine and the entire valve train is stock, fully broken-in and in good condition, ZDP content is not an issue.

However, if the engine is modified with any combination of aftermarket flat-tappet camshaft, valve springs having higher than stock pressure or higher ratio rocker arms then your friend should not use any oil that's rated GF-4/SM.

GF-2 or -3 or API SJ or SL are ok for engines having a mild cam and springs, but only if the phosphorous content is above 800 PPM.

If the engine has an aggressive aftermarket (ie: all-out racing) cam and high pressure valve springs and/or higher ratio rockers, you need an oil with at least 1100 PPM phosphorous.

Here are three choices for oil in a flat tappet engine having any aftermarket valve train parts which increase the load at the lobe/lifter interface.

Good: Chevron Delo 400 LE 10W30
Better: Vavoline VR-1 10W30 Racing Oil
Best: Red Line 10W30 Engine Oil.
 

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