Moly in Engine Oil,


Check out the OEM bulletin from Cummins. It is the Cummins Engine Oil Recommendations, Bulletin No. 3810340-02 . Its probably best if you stopped by a Cummins Dealer and purchased this bulletin- about $2 or $3.
On page 7 it has a section on FRICTION MODIFIERS states:
"There is firm evidence that certain friction modifiers, molybdenum dithiophosphate for example, can in certain formulations result in cam follower pin failure at relatively low mileage"........

From years working with engine test programs to approve engine oil formulations for API licensing, we can tell you that NO engine oil containing Molybdenum additives has been certified by the full range of engine tests necessary to gain API approval.

Molybdenum compounds in motor oils can degrade and cause bearing corrosion and is particularly aggressive towards copper. In almost all cases, any engine oil formula having "moly" will also contain a Copper Deactivator which will protect bearings from the moly compounds. The only problem, the copper deactivator decomposes at relatively low temperatures and looses it's potency after a few thousand miles.