GM's EOS oil additive?

Status
Not open for further replies.
Messages
70
Location
Louisiana
Thread starter
I purchased a couple of bottles from my local GM dealer. 16oz per bottle. I plan on using it in my 06 silverado 4.8 v8. Would you use the whole bottle or half of it in a 6qt. capacity oil pan.I'm trying it because I heard it has great anti wear properties.
 
Messages
18,449
Location
East of IGO
EOS is for the first time a new engine is fired up Especially cam in block with a non roller camshaft . It is not needed at all in your engine ,a full can will have way too much additives and can lead to combustion chamber deposits.
 
Messages
6,388
Location
Washington St.
Just why do you feel that any brand of good motor oil, right out of the bottle, isn't adequate? How many hundreds of thousands of miles do you expect to own your truck, and why do you thing your engine will show significant wear in that period (if less than 300,000 miles)? Do not think that you or any of us can home-brew better oil than the oil company chemists. If you want better oil, buy better oil.
 

JAG

Messages
5,320
Location
Fredericksburg, VA
I'd add a few ounces per OCI too. Even if it doesn't help anti-wear properties, ZDDP does double duties as an antioxidant (especially hydroperoxide destroyer).
 
Messages
1
Location
65201
Thank you JAG for the additional info From: www.slantsix.org/articles/Modern_Engine_Oils.htm …...Well, the SM spec stipulates Zinc and Phosphorus content of 0.06% to 0.08% (600 to 800 ppm). GM EOS contains 5762ppm Zn, and 6221ppm P, or 0.6%. That means in a quart of EOS, you've got about 0.192 ounce of Zn and P. It's been well documented that a 0.10% to 0.12% concentration of Zn and P is optimal for flat-tappet engines, for example in SAE papers 770087, 831760, and 2004-01-2986. To achieve 0.11% Zn and P in a 5-quart system, we would want 0.176 ounces of Zn and P. There's 0.192 ounce in a quart of EOS, but there's also 0.08% Zn and P in a quart of SM engine oil (actually, most of them run a little on the high side, as it seems, but we'll use the 800 figure). In 5 quarts of SM engine oil, therefore, you've got 0.128 ounce of Zn and P. Therefore, you're a little under 0.05 ounce short of what you want. Doing out the math and remembering that I've been rounding pessimistically, 8 ounces (1 cup, i.e., half a pint) of EOS would bring most any SM engine oil back within the optimal Zn and P content, which means that a quart of EOS would last you four oil changes. ..... IF THE WHOLE MESS OF AUTO SALES WHERE CORRECTED, your light pickups would be equipped with SERIES diesel hybrids and possibly reach 100mpg eliminating the need for emissions GIMMICKRY
 

Astro14

Staff member
Messages
11,643
Location
Virginia Beach
If this topic interests you, 12 years later, then please start a new thread on old cars, GMs EOS, or whatever aspect of this thread you were trying to resurrect. Thanks
 
Status
Not open for further replies.
Top