There is an interesting thread on Tundra Solutions concerning the use of moly grease in rolling element bearings. The argument, by a guy that says he is a lubrication engineer, is that moly is harmful to rolling element bearings. I have been using moly grease everywhere. I may change to Mobil 1 in the u-joints. Moly is definitely the correct grease for the sliding joint.

I would provide the link but you must register. I hesitate to copy and paste his write up here.

Any comments?

 

Is there really such a thing as a lubrication engineer? Well, you learn something new everyday I guess..

As far as I know, moly grease is fine to use for driveshaft components such as U-joints, slip yokes and steering knuckles. I don't know the exact details, but he may be referring to it being in the CV boot or the wheel bearings.

Bearings use more of an oil than a grease and I believe CV boots use yet another kind of grease. Don't quote me, but CV boots might use moly or a graphite based grease.

 

Check out The Society of Tribologists and Lubrication Engineers .

The argument of the guy on Tundra Solutions was that the particles of Molybdenum Disulfide in the grease are harder than the steel needles in the universal joints. When the needles roll over the moly particles it causes premature wear on the surface of the needles. The surface takes on a "frosted" appearance.

Anyway, it was the first I had heard of this and I thought it was interesting enough to put before the group.