Here is some Mobile 1 info....
Question:
Presence of Zinc in Engine Oils
Does Mobil Delvac have zinc in the oil? A lot of racers are using Shell to break in their cams in HP engines due to the zinc in the oil. It works the best. I think most oils for non-gas cars have zinc in the oil to help something?
-- Jeff Paquette, Raymond, NH
Answer:
All engine oils have an additive called ZDDP (Zinc DialkylDithioPhosphate) for wear protection. In general, heavy duty engine oils (truck oils like Mobil Delvac) have a higher level of ZDDP. Automotive engine oils generally have a lower level of ZDDP to protect catalytic systems. For details on phosphorous levels in Mobil 1 motor oils, see a related question and its answer.
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Question:
Has Zinc Been Removed from Motor Oils?
I am having thrust bearing failure in a 4.6 modified performance engine. This is a street/strip engine. Many of my friends are having the same problem. I think it is the result of the removal of zinc from the oil. I was told by two separate racing engine builders that the EPA ordered the removal of the zinc from over-the-counter motor oil. I use Mobil 1 5W-20. Is this true and do you think a zinc additive might help?
-- Randy Lovejoy, Americas, GA
Answer:
The active ingredient that you are talking about is phosphorus which is added thru a component called ZDDP. For products that meet the new ILSAC GF-4 specification the phosphorus levels for the oil must be less than 800 ppm phosphorus. The ILSAC level for phosphorus has been reduced to protect the catalytic converter and other emission protection equipment. The engine manufacturers are confident that this level of phosphorus will protect both new and older engines. However, there are Mobil 1 products which have a higher level of phosphorus (phos) and can be used in engines in racing or high performance applications; see the attached table.
check out the table attached below,you can see the zinc levels in the mobile 1 oils....
Dan